Castrovalva:

(*)ep 1 – The Doctor's footwear regenerates with him! Watch as he changes from long brown leather boots in the pre-credits sequence to brown shoes in the episode proper.
[Apparently the boots actually belonged to Tom Baker and he simply took them with him when he finished filming the regeneration scene...!]

NEW (*)ep 1 – And it's not only the Doctor's footwear that behaves strangely: Peter Davison's hair is light brown in the pre-credits regeneration sequence but changes to near-platinum blond in the rest of the episode.

NEW (?)ep 1 – When Tegan drives the ambulance away from the Pharos project guards, there's a shot of her pulling the steering wheel sharply to the right, followed by Nyssa falling into the passenger seat. However, Tegan's manoeuvre would have flung Nyssa away from the passenger seat instead of towards it.

NEW (?)ep 1 – When Nyssa closes the TARDIS doors, she says "This works the doors — that's all I know about these controls". She then immediately contradicts herself by moving around the console and turning the scanner on!

NEW (?)ep 1 – When the Doctor is levitating in the Zero Room, the shot of him overlaid onto the main picture is reversed — see the question-mark symbol on his shirt lapel, and also the parting in his hair.
[You'll already have noticed this if you listen to the DVD commentary, where Peter Davison takes great pleasure pointing it out]

NEW (?)ep 2 – Nearly 5 minutes into episode 2, while the Doctor is sitting in the wheelchair, look sharp for a whopping great boom shadow right across Peter Davison's jacket.

NEW (?)ep 3-4 – The "crazy-quilt" broken-up view of Castrovalva from the Doctor's window only occurs in one shot (the Part 3 cliffhanger) — but there are several shots on either side of it which show only the normal view out the window.

NEW (?)ep 4 – When Nyssa and Tegan bring the Zero cabinet back to the Doctor's room, Nyssa knocks on the door. If you watch carefully, you'll notice that the sound of her knocking starts before before her hand even touches the door.

(*)ep 4 – While Mergrave and Ruther are searching for the cause of the broken window, there's a scene when they look meaningfully at each other. Right before the camera cuts away, the picture wobbles noticeably.

NEW (?)ep 4 – When the tapestry starts to fade and Adric appears, the shot of Adric is reversed — his red shirt pocket appears on his right-hand side instead of the usual left-hand side.

NEW (*)ep 4 – In the final scene (as the travellers are jogging back to the TARDIS), a fence is visible on the supposedly deserted planet.
Four to Doomsday:

NEW (?)ep 1 – Two minutes into episode 1, look out for a cameo from a boom mic, appearing above Nyssa's head in the top-left corner of screen.

NEW (?)ep 1 – As the Doctor leads the others out of the TARDIS, the doors open for them without anyone going near the console.

NEW (?)ep 1 – In the room where the TARDIS lands, Tegan says "Look!" and points to the top of the stairs — but only then does the door she's supposed to be reacting to actually open!

(*)ep 1 – Tegan's sketch of "Earth fashions" is awfully quick — and awfully good. If she's that talented, what's she doing as an air stewardess?

(*)ep 1 – When Monarch tries to open the TARDIS, see if you can spot the head of a crewmember hiding behind the console in the foreground, containing the lasers commanded by Monarch.

NEW (*)ep 1 – How come Bigon and Lin Futu both speak excellent English, but the Aborigine doesn't?

(*)ep 1 – Out of literally thousands of Aboriginal languages that have ever existed, it's astounding that Tegan can speak the correct one — especially since the language in question is 12,000 years old!

NEW (?)ep 2 – The Doctor says, "...if a frog with a funny head can turn itself into a semblance of a human being in a matter of minutes, there isn't much of a limit to what it can't do". The last phrase actually means the opposite of what the writer presumably intended (that there isn't much of a limit to what it can do).
[Terrance Dicks corrected this error in the novelisation]

NEW (?)ep 2 – The Doctor says "the Mayans in South American flourished eight thousand years ago". Oops — actually, their civilisation began around 2,000 BC and (historians generally agree) reached its peak in the early centuries AD. So when they "flourished" was more like 2 thousand years ago... 3 or 4 at a push. Not 8!
[Bit sloppy of the Doc to make this mistake, considering he's probably been to visit them at some stage!]

NEW (?)ep 2 – One of the Greeks watching the Mayan dance from the balcony is wearing distinctly un-Ancient-Greek white trainers (i.e. sneakers).

NEW (?)ep 3 – When Nyssa is led out of the throne room to the Mobiliary by two of the Greek warriors, the reflection of a crew member is briefly visible as the door opens, in a panel of the corridor outside.

NEW (?)ep 3 – When the Greek warriors escorting Nyssa leave the throne room, they are not wearing their helmets. In a shot of them leading her down a corridor, however, the helmets have mysteriously appeared. When they eventually arrive in the Mobiliary, the helmets are gone again.

(*)ep 3 – On two separate occasions, the Doctor uses his sonic screwdriver to send a monopticon spinning around rapidly, both times in an anti-clockwise direction. However, the monitors in Monarch's control room show the images as if the monopticons were spinning in the opposite direction (clockwise).

NEW (?)ep 4 – When the Doctor is convincing Lin Futu to help him, watch the extra in the background as Lin Futu is asking, "How can I re-circuit Bigon without Monarch knowing?" He's just lounging there, casually watching the actors until he realises the camera's on him, whereupon he quickly starts working away again at his console!

(*)ep 4 – Look closely at the Chinese Dragons to spot the dancers underneath, dressed in their most authentic Ming Dynasty jeans and T-shirts! Even more amusingly, a Kung Fu Club sign is plainly visible in one close-up...

NEW (?)ep 4 – After the Doctor jumps out of Monarch's ship, he drifts towards the TARDIS, slows down, and stops. Since there's no air resistance (or other sources of friction) in space, the Doctor should have continued moving towards the TARDIS at a constant speed.

(*)ep 4 – And continuing the theme of dodgy physics, the scene with the Doctor space-walking and using a rebounded cricket ball to propel himself back to the TARDIS must have Isaac Newton spinning in his grave! For one thing, the Doctor couldn't have been propelled backwards that fast by such a relatively small object as a cricket ball. What should happen, if the Doctor were to actually try it, would be this: after releasing the ball in the first place, he would have started moving backwards by the action of throwing the ball (remember Newton's Third Law?). And not just moving in a straight line, mind you — he would have spun backwards in a slow cartwheel as a result of pitching the ball cricket-style, as he did. Assuming he was lucky enough to get a perfectly perpendicular bounce from that spacecraft, the ball would have caught up with him, impacting with whatever part of his body was facing that way at the time, increasing the rate of his spinning motion (but not by much, certainly nowhere near as fast as portrayed on-screen).

NEW (?)ep 4 – When the Doctor and Tegan exit from the TARDIS in the recreational chamber, they run off and leave the TARDIS door wide open — right in front of Monarch! Not only that, but when they return to the recreational chamber for the final confrontation with Monarch, the TARDIS doors have magically closed.
Kinda:

(*)ep 1 – Look very closely at the forest floors, and you'll be able to see cords (which are large power lines). The best example occurs during Part 1, in the background of the shot where the TSS is herding the Doctor and Adric towards the Dome.
[Apparently JNT noticed this during production, but it was decided to just "buy" the shot in the hope that the cables would be mistaken for tree roots(!)]

NEW (?)ep 1 – The draughts board used by Adric and Nyssa is placed wrongly. It has a light square in the bottom-left corner for each player, whereas it should be placed so a dark square is at the bottom-left.
[Though neither of them are from Earth so perhaps we can forgive them not knowing how to play draughts?]

NEW (?)ep 1 – At the Windchimes, Tegan strikes the same chime three times with a branch and produces three different notes! Also, when the Doctor has her strike two notes, and exclaims, "A perfect fifth!" the musical notes heard actually form a perfect fourth.

NEW (*)ep 4 – As the Doctor is saying "What is Karuna?" he has to pull himself up short before he falls over. Watch him glancing at the ground to get his footing!

NEW (?)ep 4 – When Adric in the out-of-control TSS is firing on Aris, the flash charges leave a small fire burning in one corner of the twig-and-branch construction enclosing Aris. You can see Adrian Mills (Aris) repeatedly glance down during the remainder of the scene, clearly worried that the fire might spread!

(*)ep 4 – In the circle-of-mirrors scene, it's very clear to see that one of the mirrors is missing (the one in the bottom-left corner of the high-angle shots). This is, of course, because the cameras doing the ground-level shots needed a gap in order to shoot the action inside the circle.

(*)ep 4 – Watch out for the incredible bouncy snake! Not to mention the wires and jaw braces which can be seen on the big snake despite the deliberate smearing caused by the overlaid video effects.
The Visitation:

NEW (?)ep 1 – In the opening scene of Elizabeth watching the fireworks in the sky, we initially see her looking out of the bottom-left corner of a window (the curtain is to her right), but when we cut to the inside of the room (as she goes off to tell the others), we see she was looking out of the bottom-right corner, with the curtain to her left.

NEW (?)ep 1 – In the first TARDIS scene, the electrical cable running along the floor from the console is very obvious — the Doctor even stands on it at one point!

NEW (?)ep 1? – The ship has supposedly crashed in the middle of a forest, but when the doors open, you can't see any forest!

NEW (?)ep 2? – At one stage Nyssa has a line referring to "Adric and Tegan", but what Sarah Sutton actually says sounds more like "Andrid and Tegan".
[Was she thinking "android"?]

(*)ep 3 – When Nyssa is pushing the sonic booster into her room, you can see that her trousers have fallen down a bit too far. She hurriedly pulls them up, making a big show of it in the process.

NEW (?)ep 4 – Both times that Nyssa switches the sonic booster on, the noise and shaking effects start too early, a moment before the switch is actually pressed.

(*)ep 4 – During one TARDIS scene with Adric and Nyssa, they mention that it's getting dark outside — and indeed, the next scene (with the horse) clearly takes place during the evening, while the sun is setting. However, in the indoor scene following that (with the Doctor, Tegan, and Mace), inexplicably there's plenty of bright sunshine visible through the window.

(*)ep 4 – Watch for the disappearing hat trick that Peter Davison does in this story. One moment he's holding it (as he's about to open the door to the bakery's back room), and in the next shot (from inside the room) as he actually opens the door, it's gone!

NEW (?)ep 1,4 – The ornaments we see in Nyssa's and Tegan's room at the start of the story have disappeared by the time we see their room again in episode four.

NEW (?)ep 4? – At one point when Adric is supposed to have a line about "the Doctor and Tegan" it comes out as "the Doctor and the Tegan".
Black Orchid:

(*)ep 1 – As the TARDIS crew arrive at the cricket match, the batsman hits the ball towards the boundary — but then the umpire signals a wide by spreading both his arms. It can't be a wide, because the batsman hit it! Furthermore, it looks like the 'wide' signal is the only one the actor playing the umpire knows — it's difficult to be 100% sure, as only one of his arms is clearly shown, but he appears to use it twice more, once when the Doctor hits a boundary and again in response to an appeal for L.B.W. as the last wicket falls. Obviously neither of those is a wide either!

NEW (?)ep 1 – During the same scene, as the Doctor & co walk towards the cricket match, you can see the film crew reflected in the car door!

NEW (?)ep 1 – Just before Ann is introduced, Peter Davison appears to be intently studying a piece of paper, which he hurriedly puts away in his inside coat pocket as the scene starts. A script page, perhaps? It certainly doesn't appear to be anything referred to in the story.

NEW (?)ep 1 – Peter Davison and Gareth Milne (playing George Cranleigh) are of noticeably different heights, yet the same harlequin costume fits both of them perfectly!

NEW (*)ep 1 – At the fancy dress party, they're all supposed to be having a jolly old time outside, yet there's obviously a Force Ten gale howling!

(*)ep 2 – The policemen from 1925 recognise the TARDIS, although TARDIS-style police boxes weren't introduced until 1929.
[Although police boxes were introduced in Sunderland in 1923 and Newcastle in 1925, they were of quite a different design. looking more like sentry boxes]

NEW (?)ep 2 – The face of the actress doubling Sarah Sutton is in plain view a couple of times as the group on the terrace watch the confrontation with George Cranleigh on the roof.
Earthshock:

(*)ep 1 – Watch the scene when the last soldier in the search party hears a noise down in the caves and turns around. By the time he does so, the androids have disappeared down a side corridor, but the shadow of one of them can clearly be seen moving along the cavern wall. The soldier would have had to have been blind to miss it!

NEW (?)ep 1-4 – Listen out for Lt. Scott's amazing changing accent! It changes inexplicably between the location scenes in episode 1-2, and his later-recorded scenes in the studio.
[OK, it's not really that inexplicable — obviously actor James Warwick forgot what accent he was supposed doing when coming back a couple of weeks later to film the studio scenes!]

(*)ep 1-4 – The Cybermen's mouth/chin pieces were originally clear plastic, but were later sprayed lightly with silver paint to avoid showing too much of the actor's mouth inside. Due to the order of filming they tend to swap back and forth during the story. See if you can spot the changes!

NEW (?)ep 1-2 – In the Episode 1 reveal shot of the Cybermen, we see three of the metal meanies gathered around their viewing console. However, after the reprise in Part 2, the third Cyberman disappears from Cyber-control and is not referred to or seen again until well into Part 3, when he gets the job of continuing the reactivation as the two "main" Cybermen go off to attack the bridge.
[Did he go for a cigarette break?]

(*)ep 2 – As the Cybermen are going through the various clips of the Doctors, before each new Doctor clip comes on, slow the tape down and you'll see a frame of the Cybermen looking at themselves in their viewing ball!
[This is certainly true on the video release — can anyone confirm if the Restoration Team fixed it on the DVD?]

(*)ep 2 – Just before he receives a message saying that the freighter has received security clearance, the Cyberleader tries to press a button on his console — and misses. But we hear the appropriate sound effect anyway!

(*)ep 3 – After one of the first battles, as the Cybermen are walking up some stairs through the dead bodies, one of them stumbles.

(*)ep 3 – As Tegan complains that she's exhausted and Scott tells her to keep her voice down, look in the shadows behind them — something that looks like a white baton is moving in the darkness. This is actually the edge of a script being held by a production crew member: as Tegan and co. climb the stairs on their way to the bridge, you can see her more clearly in the background.

(*)ep 3 – At one point, the Doctor explains the Cybermen's vulnerability to gold by stating that it "clogs their chest units — suffocates them". But later on, after the Captain says she could evacuate the the air from the hold, the Doctor says, "Unfortunately, Cybermen don't need it" — er, if they don't need air, how can they "suffocate"?

NEW (?)ep 3 – The two Cybermen observed by Scott, Tegan and co. must be having a lovely chat, judging by some of their animated hand gestures!

NEW (?)ep 3 – We have multiple problems with the scene on the bridge when the Cybermen explosively burst through the bulkhead. First, notice that the Doctor and Adric already have their arms poised to react, even before the explosion occurs! Secondly, the Cybermen sets four explosive charges around the outside of the wall, yet only the middle part of the panel is damaged... Then, the hole gets magically bigger between the explosion and a moment later when the Cybermen actually step through. And finally, as they walk through, they brush against the bulkhead which bends as if it was made of cardboard!
[Obviously if that was true they wouldn't have needed explosives in the first place — just a scissors!]

NEW (?)ep 3 – When Lieutenant Scott kills the second Cyberman on the bridge, he starts falling down way too early.

(*)ep 3 – During the cliffhanger, it's blatantly obvious that the three columns of advancing Cybermen are merely mirror images — watch the middle one's right hand disappear!

(*)ep 4 – Look at the scene after the troopers and Tegan are separated, when the troopers return to the TARDIS. There are four of them remaining at this point: the commander, a man with straight hair, a man with curly hair, and a woman. As they enter the TARDIS, a Cyberman grabs the female trooper. In the next shot (inside the TARDIS) the commander, the straight-haired man and the woman make it inside, closely followed by the Cyberman, but the curly-haired man is missing! After they leave the TARDIS and are evading Cybermen in the freighter's hold, the female trooper has disappeared, and the curly-haired bloke is back!

NEW (?)ep 4 – In the last scene of the Cyber Lieutenant in Cyber-control, the close-up of his hand operating the console doesn't match the wide shot. Look at the position of that T-shaped lever (the one that later swings down on its own after he leaves) — in one shot it's down, in the other it's up.

(*)ep 4 – As the Doctor and Tegan are being led away from the bridge, the Cyberleader loses his footing when he gets to the bottom step.

(*)ep 4 – The continents of 65 million years ago look strangely familiar...
[Hasn't the BBC effects department heard of continental drift??]

(*)ep 4 – Watch Adric as he's trying to type in the final code on the keyboard — he tentatively taps a key or two, then flinches away from the console. This is because Matthew Waterhouse knows it's going to blow up any minute, thanks to the final remaining Cyberman — though of course Adric isn't supposed to know this!
Time-Flight:

NEW (?)ep 1 – The thick snow covering the ground in the Heathrow location footage completely fails to match the stock footage of Concorde taking off.

NEW (?)ep 1,4 – Since the stairs leading down from Concorde are part of the illusion and don't really exist, how do the Doctor and co. get down to the ground without any apparent injury when they land in the past? Similarly, in Part 4, how does everyone (including all the passengers) get back into Concorde for the take-off?

NEW (?)ep 1,2,4 – Hearing the loud wooden clumping sounds as the travellers move around the supposedly sandy/rocky prehistoric wasteland brings back fond memories of Vortis and other Sixties-era planetscapes. For extra nostalgia value, watch out for the creases in the backdrop representing the sky — and if you keep your eyes at the top of the screen (during episode 1) you can even see the edge of the "sky" in a couple of scenes!

(*)ep 1 – Having travelled about 140 million years into the past, the Doctor does a pretty good job without the TARDIS to estimate that the Concorde has landed in the Jurassic period. (Actually the Jurassic ended approx 145 million years ago, but what's 5 million years between friends?) But then he blows his geologist cred completely by saying, "We can't be far off the Pleistocene era" — whereas in fact they're over 137 million years off! The Pleistocene epoch (not "era") began about 2.5 million years B.C.

(*)ep 1 – As the Doctor and co. search for the original Concorde, Captain Stapley fails to prove his eyesight airworthy when he manages not to notice the missing plane straight in front of him (Tegan, who is standing further away, has no trouble spotting it).

NEW (?)ep 1 – When the TARDIS is supposedly being dragged away by the passengers, it's clearly been placed on a wheeled platform of some kind — it's smoothly gliding along in a totally unrealistic way.

(*)ep 1-2 – Stapley and Nyssa warn the Doctor about the Plasmatons appearing behind him before they're actually visible on screen.

(*)ep 2-3 – Anthony Ainley has trouble getting out of his Kalid disguise.

NEW (?)ep 3 – At the start of this episode, the smoke that was previously filling Kalid's crystal ball is suddenly completely gone after the Master reveals himself.

(*)ep 3 – Watch out for the Master accidentally activating his TCE (just as the Doctor says the line "No heroics") — so technically, Stapley and friends should be dead!

NEW (?)ep 3 – Watch the door control lever during the scenes with Stapley and Bilton observing the Master's attempt to fly the TARDIS. When Stapley and Bilton first enter the TARDIS, it's in the 'down' position. Then when the Master enters, it's suddenly in the 'up' position, and he pushes it down to close the doors. Later, when the Master finds he can't make the ship work, the door control is inexplicably 'up' again — so he can slam it down and storm out!

(*)ep 3 – In the scene where Nyssa is about to be absorbed by the Xeraphin into their casket, she's standing in front of it glowing in a beam of pale light. While she's standing there shouting, a human hand briefly emerges from the sarcophagus, and then falls back down.

(*)ep 3 – When Nyssa says "It seems like we're winning" in the Xeraphin chamber, you can see the boom mike shadow on the wall behind her.

NEW (*)ep 4 – The Doctor comes out of the TARDIS, telling Tegan to come with him. She runs out after him, looking back over her shoulder, and smacks right into the Doctor. He grabs her to stop her falling, but you can tell by her face how much the whole thing took her by surprise.

NEW (*)ep 4 – As the Master and the passengers emerge from the Master's TARDIS, walking on what's supposedly the ground (but is actually a bendy bit of set), the top of the Master's TARDIS jiggles.

NEW (?)ep 4 – When the Doctor and co. see the Master is stranded and go over to confront him, Scobie isn't wearing (or carrying) his jacket. But when the group arrives in front of the Master, Scobie suddenly has his jacket on again.

(*)ep 4 – When Captain Stapley's Concorde finally manages to take off from 140,000,000 B.C., we see hazy stock footage of an airborne plane imposed over the prehistoric set. While the plane is lifting off, you can see what appears to be a crow flying across the screen from right to left. Now, while crows were quite common in 1982, you'd hardly expect to see one in the Jurassic era!
[Though if I was feeling generous, I could point out that it's believed the first birds did appear during the late Jurassic era, so perhaps it could be something like an Archaeopteryx instead of a crow!]
Arc of Infinity:

NEW (?)ep 1 – Robin and Colin enter the crypt via the stairway behind the fountain, and Colin closes the iron gate behind them. But as they walk down the stairs, the gate can be seen in the background swinging open again.

(*)ep 3 – Leonard Sachs as Borusa stutters most amusingly on the word "permit" while uttering the line "Only the gravest emergency would permit me to do as you want".

NEW (?)ep 3-4 – Part 3 ends with the Castellan accidentally shooting Hedin, followed by the Doctor's pronouncement that "Omega controls the Matrix". After the reprise in Part 4, the scene continues on, but the Castellan, his guards, and Hedin's body have all suddenly and mysteriously vanished...

(*)ep 4 – Producer John Nathan-Turner can be seen passing behind the telephone box as the Doctor is consulting the phone book (he's wearing a sheepskin coat). This qualifies as a blooper because it was supposedly accidental — he was apparently shooing away tourists at the time.
[Though JN-T himself subsequently claimed that it was a deliberate Hitchcock-esque cameo (a likely story!)]

NEW (?)ep 4 – When the hostel receptionist gives the Doctor the note addressed to Tegan, he reads it and then puts it down on the counter. Unfortunately the paper doesn't lay flat, but "sits up" facing the camera, revealing that it is, in fact, completely blank!

NEW (?)ep 4 – The location filming in Amsterdam must have been on a tight schedule — Peter Davison while playing his Omega "doppleganger" clearly thought he'd save time by simply pulling the gardener's overalls over his Fifth Doctor outfit — watch out for his distinctive stripey trousers poking out around the ankles as he runs along the street!
Snakedance:

NEW (?)ep 3 – In the marketplace, Lon picks up the candlesticks twice: once while Ambril is watching the puppet show and again after the end of the show.

NEW (?)ep 4 – The wall containing the snake carving wobbles visibly as Lon crashes into the Doctor (while trying to stop him from pulling out the Great Crystal).
Mawdryn Undead:

NEW (?)ep 1,2 – The door to the Headmaster's office doesn't fit its frame very well! There's a very obvious wedge-shaped gap above the door when it's closed, through which light can be seen.

(?)ep 1 – When the Doctor and Turlough are about to leave the TARDIS to disable the transmat signal on Earth, the Doctor accidentally knocks against the door lever, which starts slipping down, and he has to move quickly to pull it back to the 'up' position.

NEW (?)ep 1 – After the Doctor and Turlough leave the TARDIS, Tegan and Nyssa carry a couple of small stools into the console room and sit down facing the camera. This seems pretty unremarkable, until you realise that in this shot the camera is taking the place of one of the console room walls. So from Tegan & Nyssa's point of view they've both just sat down directly facing a blank wall. Why would anyone do this??

NEW (?)ep 2 – When Tegan and Nyssa drag Mawdryn into the TARDIS, Tegan jogs the console with her shoulder, causing it to move out of position a little.

NEW (?)ep 2 – In Turlough's dream sequence with the Headmaster and the Black Guardian, the shots of the sleeping Turlough in the middle of the sequence show the pillows in a completely different position to those at the beginning and end of the sequence.

NEW (?)ep 3 – When Turlough is telling the Black Guardian (referring to the TARDIS console) "I can operate it if you show me how!" he slams his hand down on the console hard enough to make it wobble hugely back and forth.

NEW (?)ep 4 – Standing in the TARDIS doorway, the Doctor tells Turlough to find the Brigadier and transport him in the capsule, then quickly turns to rush back inside. Unfortunately for Peter Davison, he forgot that only one of the police box doors was open, and he slams straight into the edge of the closed left-hand door!
[Ouch...]

(*)ep 4 – While talking to Turlough in the TARDIS, the Black Guardian appears to spit on himself.
Terminus:

(*)ep 1 – Watch where Nyssa accidentally drops her book in the corridor of the Lazar ship. Some poltergeist has moved it at least a yard by the time the Doctor finds it ten minutes later.

(*)ep 2 – Near the end of Part 2, there's a scene where the Doctor and Kari are walking along a sort of scaffolding towards some stairs. We see them about to descend and the camera pans down to Valgard. As he moves towards the bottom of the staircase a foot can clearly be seen up towards the top. Then, a small superimposed step is clumsily matted over the foot. It even moves with the shot!
[Obviously the special effects guys tried to cover up the foot. In fact, they made it worse by attracting attention to it, the fools!]

NEW (?)ep 4 – Olvir appears completely oblivious to the sight of the gigantic Garm and the sound of Nyssa's screams at the start of episode four, even though they're only about a metre from where he's standing. He doesn't even look at the Garm as it walks away!

NEW (?)ep 4 – Bor pronounces Eirak's name as "EYE-rack" instead of "AY-rack" as everyone else in the story does.

NEW (?)ep 4 – Does Tegan really stop the space liner's launch just by pounding on the ship's console as if it was an old TV...?

NEW (?)ep 4 – At the end of the story, the Doctor asks Valgard to take him and Nyssa to the Terminus engine room, since "there's still a lot to be done." Then in the next scene, for no apparent reason, they're back on the liner (with the Doctor still telling Valgard there's a lot to be done) and running into Tegan so that Nyssa can bid them farewell! Some mistake, surely?
Enlightenment:

NEW (?)ep 1 – Watch Mark Strickson sitting at the chessboard, waiting for his cue to sweep the pieces to the floor when the TARDIS lurches.

NEW (*)ep 1-4 – As the First Mate, Marriner should have three stripes, not two.

(*)ep 1 – When the ship experiences turbulence, the liquid in the glasses doesn't.

(*)ep 1 – Early on in the story, when the sailors in Striker's ship are running up the stairs, one of them stumbles.

NEW (?)ep 3 – When Turlough jumps off the railing into space, it bends beneath his weight and shakes visibly.

NEW (?)ep 3 – On deck, Tegan says "I must go to [the Doctor]", then immediately contradicts herself by sitting down to have a long conversation with Marriner.

NEW (?)ep 3 – In some scenes with Wrack, Mark Strickson as Turlough evidently forgot to take off his wedding ring!

NEW (?)ep 3 – When one of Wrack's sailors locks Turlough in the ion chamber, he misses the last lock on the door (though we still hear the sound effect). He manages to kick it closed on his second attempt.

(*)ep 3 – When Tegan enters the wheelhouse on Wrack's ship, she's talking (with her eyes open) when she's frozen by Wrack. We then cut to another shot of Tegan, now with her eyes closed. But if she was frozen, how could she close her eyes?

NEW (?)ep 4 – Why don't Wrack and her first mate vanish the instant they are pushed overboard the Buccaneer, like the Eternals who were forced to walk the plank earlier in the story?
The King's Demons:

(*)ep 1 – French was still the language of the English royal court in the early 13th century, so why is Sir Gilles the only one who speaks it?

NEW (?)ep 1 – At the jousting field, the King raises his left hand to signal to the herald. However, in the next shot, when the King drops his hand to start the joust, it's his right hand that is raised.

NEW (?)ep 1,2 – The iron maiden (in reality the Master's TARDIS) is clearly lacking any inward-pointing spikes, rendering it fairly useless as an instrument of torture!

(*)ep 1 – Kamelion (as King John) is seen playing a lute, but he fingers it as though it were a guitar. The lute is not played like a guitar! (Compare with the real lutist, seen at the very beginning.)

NEW (?)ep 1 – After King John completes his song, the court bursts into applause and other expressions of approval — and someone in the crowd can be heard getting into the spirit of things a little too enthusiastically, with "Oh, yeah!"
[No doubt followed by "Right on, man!"]

NEW (?)ep 2 – When the Doctor finds Kamelion (in his android form) playing the lute, it's quite obvious that the lute is just resting in the robot's arms — neither of its hands is touching the instrument.

NEW (?)ep 2 – The supposedly-dead Sir Geoffrey can be seen to blink as Ranulf and the others go rushing off (as Ranulf says "Bring the rogue!")
The Five Doctors:

(*) The Doctor explains that the Eye of Orion feels like Earth after a thunderstorm because of the "high bombardment of positive ions." Nice try Doc, but it's actually negative ions which are present in large quantities after a thunderstorm.

(*) After the obelisk gobbles up the third Doctor and Bessie, it moves off — but you can see Bessie remain there for about half a second before she fades away.
[This blooper isn't visible in the Special Edition, due to the re-edited special effects]

(*) If the High Council has the power to offer the Master a new lifespan (in return for rescuing the Doctor), why does Borusa, President of the High Council, choose to pursue immortality in such a roundabout way?

NEW (?) The Cyberman that grabs the Brigadier's arm through the hole in the wall is clearly wearing jeans!

NEW (?) Trudging through the Death Zone with Susan, the first Doctor pauses to rest against a boulder. Unfortunately, it turns out to be of the lightweight polystyrene variety, and wobbles noticeably.

NEW (?) When the First Doctor and Susan stop to rest in the Death Zone, Susan suddenly notices the TARDIS and points it out with surprise and delight. Then we can see it's standing in an open space maybe ten metres in front of them. They should have seen it from miles away!

(*) When the Master arrives in the Death Zone, he's wearing a rather fetching black cloak — which he didn't have a few moments earlier when he stepped into the transmat.

NEW (?) Watch Elisabeth Sladen as she and Jon Pertwee drive off after talking with the Master — she's turning her head from side to side and flinching away, anticipating the explosion that's about to go off in front of Bessie.

NEW (?) When the second Doctor and the Brigadier fight off the Yeti, the creature triggers a rockfall. As the "rocks" descend, you can see that they are very obviously attached to a piece of netting.

NEW (?) The second Doctor sees the Brigadier's torch-flame fluttering and deduces "where there's a wind, there's a way" — except that the flame only flutters in close-up; in the wide shots it rises straight up.

(*) The Cybermen following the Master into the Dark Tower must have been blind not to see the First Doctor and Tegan as they run for cover.

NEW (?) The VHS Special Edition uses a different take of the chessboard scene in the Dark Tower where Richard Hurndall recites an incorrect value for pi.
[This was corrected in the DVD version]

NEW (?) In the first scene where he plays with the Harp of Rassilon, the Doctor manages to get two different notes from the same string!
[This blooper was fixed in the Special Edition]

(*) After Borusa uses his powers to freeze the Doctor's companions, they all remain completely motionless — except the Brigadier, who turns his head to watch Borusa go.

(*) When Rassilon is discussing giving Borusa immortal life, Borusa has his hand dramatically poised — and when he lowers it, it bangs into Rassilon's coffin.
Warriors of the Deep:

NEW (?)ep 1 – In a couple of the early TARDIS scenes, the electrical cable powering the console is clearly visible, running along the floor and out through the wall of the set.

(*)ep 1 – Look out for Icthar's (human) eyes, which can clearly be seen blinking through his costume.

(*)ep 1,2 – Tegan acquires a bra between Parts 1 and 2.

NEW (?)ep 2? – If you can, freeze frame and take a close look at the instructions on the two airlock doors: The one on the left says: "TO OPEN: Open other door first". The one on the right says... exactly the same thing!

NEW (?)ep 2 – The fact that the airlock door that falls on Tegan is just a large piece of soft foam rubber is hideously obvious.

NEW (?)ep 3,4 – The Sea Devil helmets almost never sit straight on the creatures' heads, lending them a ridiculously drunken air during the attack on the airlock or many of the scenes on the bridge.

(*)ep 3,4 – The Silurian costumes come apart in places, and white T-shirts can be seen through the holes!
[Many such problems were caused by the fact that this story fell more behind production schedule than any other. Apparently some takes were, as far as the actors knew, just full-dress rehearsal.]

NEW (?)ep 4 – Watch the Sea Devils bringing the Doctor and Tegan into the bridge — the last one through appears to catch his foot in the door and he bends down (in full view of the camera) to try and fix it. Not very successfully, as a later shot in the scene shows him looking distinctly pigeon-toed...

(*)ep 4 – On the bridge, when Icthar says he will talk to the Doctor and dismisses the Sea Devils, two of the exiting Sea Devils manage to walk into each other.

NEW (?)ep 4 – As Turlough is pushing Preston into the ventilation shaft, the entire wall section wobbles noticeably.

NEW (?)ep 4 – About 3 minutes from the end, keep an eye on the bottom right of screen to see a disctinctly human hand keeping hold of one of the Sea Devil's guns.
[Did the Hand of Sutekh fall through a time rift to 2084?]
The Awakening:

NEW (?)ep 1 – Once again, the electrical cable powering the TARDIS console makes an appearance.

NEW (?)ep 1 – As the Doctor watches Will emerge from the priest-hole, look over his shoulder at the far corner: someone or something appears to be moving in the shadows...

NEW (?)ep 1 – When the crack in the wall breaks open, the wall wobbles rather obviously.

NEW (?)ep 2 – What happens to Tegan's bag when the plague victim transforms into the cavalier? It doesn't appear to be left behind, even when the cavalier later vanishes.
Frontios:

(*)ep 1 – As Captain Revere sees the earth moving beneath him, the fingers of a crew member can be seen giving it a helping hand.

NEW (?)ep 1 – Yet again, the TARDIS console's power cable is clearly visible in a couple of the early scenes, running along the floor of the room and out the back of the set.

NEW (?)ep 1 – As Brazen enters the stateroom to tell Plantagenet about the arrival of the travellers, the doorway wobbles rather badly.

(*)ep 1,2 – When Plantagenet is hit by a meteorite fragment at the end of Part 1, he clutches the left side of his chest — but when we see him collapse in Part 2, he clutches his right side. Then, a few scenes later, when his shirt has been removed, we see that the wound is located centrally on his torso.

NEW (?)ep 2 – In the tunnels, the Doctor hides the lamp he's carrying under his coat when he hears someone approaching, which turns out to be Mr. Range. However, there's no visible change at all in the actual lighting of the scene, from when he's carrying the lamp, to when it's under his coat, to when he takes it out again.

(*)ep 2 – When Tegan runs out of the medical shelter (being chased by Brazen and some guards), she locks the door by putting a rod through the two handles on the double doors. Later in the episode, when we see the guards trying to break the doors open, the rod is on top of the handles, not through them.

NEW (?)ep 4 – The end of a boom-mike drops briefly into shot in the first scene in the incomplete TARDIS console room, just before Plantagenet says, "Turlough has remembered the secret of the Tractators".

(*)ep 4 – In one scene aboard the still-incomplete TARDIS, you can just barely see the central column of the console rise to its 'up' position on the left side of the screen. How could the column move if none of the controls were operative?

NEW (?)ep 4 – All through the climactic scene the Gravis's antennae are wildly askew, and he collapses onto the console with his left antenna pointing downwards. Yet a moment later, when the Doctor goes over to examine his inert form, both antennae are pointing straight up.
Resurrection of the Daleks:

NEW (?)ep 1 – In the first scene with Mercer and Styles, an extremely blatant boom-mike shadow lingers over Mercer's face as they wait for the laboratory door to open.

NEW (?)ep 1 – In the battle at the airlock, a close-up of one of the Daleks shows its top lifting up just as it fires.

NEW (?)ep 1 – On the Dalek ship, Turlough watches a Dalek go through a doorway into the time corridor area (a completely white room), after which the door slowly descends behind it. However, the door is so slow that the Dalek visibly comes to a halt in what is obviously just a corner of the studio — watch its shadow reveal the previously invisible join between wall and floor!

(*)ep 1 – Somebody forgot to include Leslie Grantham in the credits.
[This blooper applies only to "Part 1" of the originally-transmitted version of this story, where Parts 1 and 2 were combined into a single 45-minute episode]

NEW (?)ep 2 – The Dalek that is pushed by the Doctor and co. towards the warehouse first-floor window has a normal glossy grey paint job. However, the exterior shot (as it emerges, falls to the ground and explodes) shows a rather battered-looking Dalek with a dull matt finish and very crude, distorted neck rings.

NEW (?)ep 2 – When a force of Daleks invades the warehouse, three Daleks get into the time corridor aboard the ship, but four emerge from the other end!

(*)ep 3 – In one of the scenes of the Doctor in the mind probe room, there's a body in the background (supposedly the duplicate of Turlough, in suspended animation). But keep an eye on its hand, and you'll see it moving.

(*)ep 3 – When Tegan digs out one of the canisters, she mentions how light they are and tosses them about. However, when they arrive on the Dalek ship it takes two troopers to pick one up.
[Must be all that weight training they put air hostesses through!]

(*)ep 3 – Somebody forgot to include a picture of Leela amongst all the other companions in the mind-drain sequence.
[Technically this is breaking my rule about "no cross-story bloopers" but it's such an egregious (and easily avoided) error, I can't let it slide...]

(*)ep 4 – As Mercer and Stien escort the Doctor to confront Davros, watch the wall behind them as the door slides shut. The wall is semi-transparent, letting you clearly see the silhouette of a stagehand push the door shut, straighten up, and walk off.

NEW (?)ep 4 – When Mercer shoots the two guards outside the laboratory, one of them falls against the wall as he dies, and makes it wobble hugely. Stien does the same as he collapses against the wall shortly afterwards.

NEW (?)ep 4 – Also in this gun battle, the "wrong" sound effect is used when Stien shoots the two troopers — his gun sounds like one of the space station guns (like the one Mercer just used) instead of its normal sound.

NEW (?)ep 4 – Just like in episode 2, three Daleks enter the time corridor for the final battle but four emerge in the warehouse. Note, too, that one of the four Daleks is of the non-moving kind — it can be seen "frozen" in the background of several scenes in the battle.

NEW (?)ep 4 – Davros supposedly crushes one of the virus capsules against a benchtop to release the contagion within. However, the capsule is already smoking well before it touches the bench.

NEW (?)ep 4 – The TARDIS lands in the ground floor of the warehouse, where Tegan and Turlough retrieve one of the virus canisters. However, when the Doctor takes the canister out to deal with the Daleks, he walks straight out of the TARDIS into the battle area — which is on the first floor!
Planet of Fire:

NEW (?)ep 1 – Yet again, the electrical cable powering the TARDIS console is very obvious in several scenes, especially when Turlough discovers Kamelion plugged in to the console.

(?)ep 1 – You can see the mountains move against the desert floor when the Doctor is walking on the surface of Sarn.
[This appears to have been fixed for the DVD edition?]

(*)ep 1 – Peri dries off awfully quickly between nearly drowning and being carried into the TARDIS by Turlough a couple of minutes later. And in her next scene, her hair is back to being perfectly styled, too.

(*)ep 1-4 – Watch how the question marks on the Doctor's braces keep changing the way they face, depending on whether Peter Davison is appearing in the studio or on location.

NEW (?)ep 2 – When the "Kamelion-Master" forces Peri out of the TARDIS with him, they leave the door open. But when Kamelion gets hit by the falling pillar, the TARDIS can be seen in the background with the doors closed. Later, when he gets up and looks back at the TARDIS, the door is open again.

NEW (?)ep 3 – The Master's TARDIS is amazingly similar to the Doctor's — even down to the electrical cable running along the floor (except that it's black this time). It's especially obvious in the scene where Peri and Kamelion bring in the "control box".

NEW (?)ep 3 – At the cliffhanger to Part 3, we see the Master turn around to face Peri twice — once in close-up, and again over Peri's shoulder as she looks into the mini-laboratory.

NEW (?)ep 4 – The door to the Master's "stone pillar" TARDIS doesn't close properly when Kamelion forces the Doctor, Peri and Amyand out at gunpoint.
The Caves of Androzani:

(*)ep 1 – The Doctor and Peri are exploring the cave system when Peri falls through a hole and out of sight, supposedly down a slope and into a spectrox nest. But after just enough time to say "boing," watch as Nicola Bryant's head makes a quick reappearance!

NEW (?)ep 1 – In the first scene with the gunrunners, when Stotz tells Krelper, "Someone's coming!" and gets up, the 'rock' he was resting against wobbles noticeably back and forth.

(*)ep 1 – Morgus's remote control quite blatantly belongs to a twentieth-century television set. Admittedly, the company logo has been taped over — but the volume, brightness and contrast controls are clearly visible in one close-up.

(*)ep 1 – When the gun-runners are throwing the cases of guns off the catwalk, one of them gets a little stuck and has to be pushed again.

NEW (?)ep 1 – In the same scene, Maurice Roëves' head collides with one of the cases, and he looks up with a startled expression at the extra pulling it towards him!

NEW (?)ep 1 – The Doctor muses, "Morgus said that spectrox was the most valuable substance in the Universe". However, we heard the entire video conversation between Morgus and Chellak, and Morgus said no such thing!

NEW (?)ep 1-4 – Jean Peyre's credit for Design Effects misspells his name as "John Peyre" on all four episodes.

NEW (?)ep 2 – In Sharaz Jek's confrontation with the Doctor (where he calls the Doctor a "prattling jackanapes") his collar comes undone and hangs loosely for the next few scenes.

NEW (?)ep 2 – In the android's-eye view of the Doctor's two hearts, not only are the hearts oddly far down in the Doctor's abdomen, but they are also clearly outside his coat...

(*)ep 2 – Maurice Roëves (playing Stotz) screws up the line, "All right, then, where's the two kilos?" He seems to start saying "spectrox" before switching to "two".

NEW (?)ep 2 – Watch how, because the Magma Beast moves so slowly, the gunrunner who gets caught by it has to actually shuffle backwards to get into its clutches!

NEW (?)ep 3 – When the Doctor is chained up on Stotz's ship, pause the DVD when he pulls out the first restraint. You'll see it remains attached to the chain, even though we hear the sound effect of it flying across the room and hitting the floor.

NEW (?)ep 3,4 – At the cliffhanger, when the gunrunners cut through the door, the cutaway shots of the blowtorch (or whatever) burning through it show a door panel which is different to the actual door we saw earlier — it is obscured at the lower right by a diagonal piece of foreground set, and there is no locking device mounted next to its upper right-hand side. But in the continuation of the scene in Part 4, the door panel with its cut-out section is now magically seen to be in its proper place.

NEW (?)ep 4 – The wall of Jek's HQ wobbles as Jek pushes Chellak out into the mud-burst.

(*)ep 4 – When the Doctor is in the cave getting milk from the Queen Bat, the shot has been reversed — you can tell because the question marks on the Doctor's collar are backwards. This also happens when he uses the last of the oxygen on the way back.

(*)ep 4 – As the Doctor is escaping from the gun-runners, his coat is stained on the front of the right shoulder by a mud-burst. But shortly afterwards, when the Doctor is climbing down to find the Queen Bat, his coat is completely clean. And then, while he's actually extracting the Queen's milk, the stains have magically re-appeared — only to disappear again as he climbs back up the rock face afterwards. And no prizes for guessing what happens in the next scene — yes, the mud stains reappear!

(*)ep 4 – Watch out for the mouseholes visible in the TARDIS during the regeneration!