Power of the Daleks:
ep 5 -	The fourth Dalek has trouble exiting through the arch. (He obviously needs to lose some weight.)
ep 5 -	This story is another fine demonstration of the art of making four Daleks look like an army by having them circle around the set a few times. Note the delay between the fourth Dalek exiting and the "fifth" Dalek entering.
ep ? -	And in another attempt to conceal the chronic Dalek shortage, spot the blatant use of photographic blow-ups in place of real Daleks.

The Highlanders:
ep ? -	Ffinch threatens his men with 300 (!) lashes each -- is he trying to punish them or turn them into mincemeat?

The Underwater Menace:
ep 3 -	At the start of this episode, you can hear the director (or possibly the PA) calling the shots very audibly.
ep ? -	Zaroff goes "Oooh" when Victoria hits him with a boulder. Kinky devil.

The Moonbase:
ep 2 -	When a Cyberman shoots at Polly (she is tending Jamie at the time), he misses, but Polly falls over anyway.
ep 2 -	The Cyberman that gets off the bed in the sick-bay nearly sends the whole thing flying.
ep 4 -	After Dr. Evans knocks out the Gravitron operator, he takes his hat and puts it on backwards. Next time we see him, it's on the right way around - demonstrating an admirable amount of fashion sense, despite being infected by a deadly virus.
ep 4? -	When the Cybermen blast a hole in the dome, they also blow a few holes in the story's credibilty - like, how can such a powerful laser only make a small hole in the plastic dome? Why does the air get sucked out into space so slowly? And just how long would that flimsy tray really hold out against a total vacuum? (Anybody have a spare moonbase I can borrow, to test this out for real?)
ep ? -	Cockney sailor Ben inexplicably becomes a scientist for the duration of the story -- so a bloke who normally thinks that a particle accelerator is a type of hoover suddenly knows that interferon is a viral antibody and that nail polish remover contains acetone. (For this one, you can blame Jamie's last-minute addition to the cast, which meant that lines had to be moved around between characters.)

The Macra Terror:
ep 1,4 -	Chicki is played by two different actresses in episodes 1 and 4.
ep ? -	When Medok is summoned to provide an alibi for the Doctor, why does the Doc tell the Pilot not to believe everything Medok says?

The Faceless Ones:
ep 1 -	Watch the background as the Doctor, Jamie and Polly decide to go to the main airport building after finding the dead body - you can distinctly see a shadow passing behind the upper portion of the door.

The Evil of the Daleks:
ep 2 -	As the Dalek questions Victoria, you can see a camera lens quickly sneak into the left of the shot and withdraw again just as quickly.
ep 2 -	At one point, Professor Maxtible calls Edward Waterfield "Whitefield".
ep 7 -	Patrick Troughton stutters amusingly when he says: "I wonder what the doo-daleks are d-doing."

Tomb of the Cybermen:
ep 3 -	The scene where Toberman is lifted up in the air by the Cybercontroller features an embarrassingly large and painfully visible safety harness.
ep 3 -	Just after our heroes close the hatch on a Cyberman who then punches at it, we see the same Cyberman appear at the bottom of the ladder with the sleeve of his costume obviously giving way around the shoulder.
ep 3 -	During the same scene, a mysterious human voice goes "Ooooooooh" over the soundtrack. (It's not any of the characters on-screen, and it doesn't sound like the Cyberman.)
ep 3 -	The end of Klieg's X-ray laser flies off when he first fires it. Clearly they don't make futuristic weapons like they used to.
ep 4 -	When the hatch is being closed for good, Jamie stumbles and nearly knocks Victoria over.
ep 4 -	When Toberman lifts up the Cybercontroller, it's all too obviously an empty costume.

The Abominable Snowmen:
ep 1 -	From inside the TARDIS, snow can be seem through the scanner, but when the travellers step outside, the surroundings are totally flake-free.

The Ice Warriors:
ep 1,6 -	In episode 1, the TARDIS materialises on its side, but at the end of the story it dematerialises right side up.
ep 1 -	Clent gets it wrong when explaining how the Ice Age came about. He says that too many plants were destroyed, and as plants produce carbon dioxide, that meant a shortage of CO2 in the atmosphere, hence the Ice Age. However, plants use up CO2, so getting rid of them would raise the temperature (under current scientific thinking, anyway - this is the same principle behind the greenhouse effect). Poor old Clent obviously wasn't paying attention in science class.
ep 4 -	Another gas-related blunder occurs when it is stated that Mars has an atmosphere mainly composed of nitrogen. In fact, it's 95% carbon dioxide and only 3% nitrogen.

Enemy of the World:
ep 3 -	It's interesting to observe that practically every sound in this episode has been redubbed and as a result is out of synch - sometimes quite badly. An example is when Milton Johns has his thugs break into Giles Kent's trailer - there's a three-second lag between the breaking of the plates and the sounds they make. Or maybe the sound guy was sitting too far away (like, 10 miles away)?
ep 4 -	Listen up for when Colin Douglas manages to mix up his lines (asking the right questions in the wrong order) and gets a series of puzzled silences from his co-stars.

The Web of Fear:
ep 1 -	At one point while the TARDIS crew are looking at the scanner, Jamie rests his hand on the console, but pulls it away suddenly as if it was red-hot.
ep ? -	Listen out for the moment when Patrick Troughton calls Victoria "Debbie".

The Wheel in Space:
ep 6 -	Patrick Troughton makes the mother of all Freudian slips (no pun intended) when telling Leo Ryan that many lives will be lost unless they "switch over to sexual air supply". (Don't ask me what he was supposed to have said.)
ep 6 -	The characters in this story keep referring to 'meteorites', which is incorrect. They should be called 'meteors', as they only become meteorites after they enter the Earth's atmosphere.

The Dominators:
ep 2,3,5 -	The zip on the back of Zoe's Dulcian costume causes her quite a bit of trouble, as it comes undone on more than one occasion (for example, when the survey headquarters is being destroyed by the Quarks).
ep 2,4 -	Toba proclaims on two separate occasions that the Dominators are "masters of the ten galaxies", but while taking over the Dulcian council, Rago more modestly claims that the Dominators "control an entire galaxy".
ep 3 -	There is no "Episode 3" caption at the beginning of this episode.
ep 4 -	As Jamie and Cully try to get out of the bomb shelter, the rubble which was blocking the hatch suddenly vanishes as they climb out.
ep 5 -	As the Doctor runs towards the Dominators' spacecraft to plant the atomic "bomb" on board, the camera strays a little too close and the face of Patrick Troughton's stunt double can clearly be seen.

The Mind Robber:
ep 1 -	When the Doctor pushes Jamie & Zoe back into the TARDIS, the caption "Producer, PETER BRYANT" is visible on the TARDIS scanner.
ep 1 -	In the same scene, look at Zoe's back. As the Doctor pushes her back into the TARDIS, he presses so hard that he leaves a handprint on the back of her jumpsuit which stays visible for several minutes.
ep 1,2 -	After the TARDIS has been ripped apart, we see the console floating about with Zoe and Jamie sprawled over it. When you see it from a distance, Zoe is lying on her right side (legs going off to the left), but the close-up shot has her lying on her left side (legs going off to the right). The camera switches between these two shots a couple of times, so this becomes quite noticeable.
ep 2 -	Jamie's voice at the beginning of the episode clearly belongs to Hamish Wilson and not Frasier Hines. (Jamie supposedly gains his new voice only after the Doctor incorrectly reassembles his face later in the episode.)
ep 2,3 -	No wonder the Doctor doesn't get Jamie's face right the first time - Fraser Hines's features are only included in the second set of choices.
ep 3 -	After the Doctor, Jamie and Zoe enter the house leading into the labyrinth, the wooden door creaks shut beind them -- but the sound cuts off and repeats itself halfway through. The door is well shut by the time the sound effect finishes.
ep 3 -	The map of the maze displayed on the Master's screen doesn't correspond to what Zoe says about following a pattern of 1 left turn, 2 right turns, 3 left turns and so on. Judging from the map, if the Doctor and Zoe had gone the way Zoe claims, they would have made it to the centre of the maze after the second right turn.
ep 3 -	The second time Jamie uses the tickertape, he reads it upside down. He stands in such a way so that the newly printed tape comes out to his right - which means the text must be upside down, unless the tickertape is printing the story backwards! (If you're in any doubt, the earlier shot of Jamie using the tickertape shows him reading it from the correct side.)
ep 4 -	It's painfully clear that the shelves and books in the library are just cardboard cut-outs. Look at how the shadows fall on them.
ep 4 -	When the Doctor & co. first meet the Master, he boasts "For twenty-five years I've delivered five thousand words every week!". Zoe replies, "Why, that's well over half a million words!". It certainly is -- in fact, it's six and a half million words. (Zoe is obviously thinking in non-Aristotelian arithmetic.)
ep 5 -	When the Doctor and Master hold their climactic battle of wits, the Master manages to spit all over the place while uttering the line "Change weapons to Destructor Beams!". Childish, I know, but somehow amusing.

The Invasion:
ep 2 -	In one scene, Zoe mispronounces 'integer' -- using a hard 'G' instead of a soft 'J'.
ep 3 -	When Packer is sent to see Professor Watkins, he gets into the lift and pushes the button for the 3rd floor. Later, the Doctor and Jamie escape while being led to the professor, and flee into the lift. When the Doctor tries to sabotage it, Jamie complains "but we're 6 floors up!", and Packer confirms a few minutes later that they are indeed on the 6th floor -- so obviously that's where the professor is. (Perhaps the toilet is on the 3rd floor?)
ep 3 -	When Jamie and the Doctor are climbing up the lift shaft to escape from the I.E. henchmen, look at the cables behind them. Considering they're supposed to be holding up a lift, the cables look worryingly loose. (Clearly they should have taken the stairs.)
ep 5 -	After Vaughan has consulted with the Cyber Controller, he sits down and talks to Packer. Look behind Vaughan at this point and you'll notice that the panel concealing the Cyber Controller has an awful lot of trouble closing.
ep 7,8 -	Why exactly do Cybermen need lace-up shoes? (You can see them in close-up while they're marching through the streets of London.)
ep 8 -	The Cyberman falling from the roof is plainly just an empty costume.
ep ? -	When the Cyberman comes out of the box (when they try to use the Professor's machine on him), part of the fabric gets stuck to him. The camera switches to a view of his back, and you can see the fabric being pulled away.

The Krotons:
ep 1 -	At the very start of the story, watch out for the sliding door which refuses to open.
ep 1 -	After the Doctor, Jamie and Zoe leave the TARDIS, they start to climb some rocks -- but Fraser Hines comes down too fast and crashes into Wendy Padbury, who is thrown back several feet.
ep 4 -	When one of the Gonds has his legs trapped under a rock, just before the Doctor and Zoe can help him he shifts his legs slightly and the "rock" wobbles considerably. It's then quite amusing to watch Pat Troughton and Wendy Padbury pretend the lump of polystyrene is heavy.
ep 4 -	While Jamie and Beta are making the sulphuric acid, at one point they walk backwards into each other. At this moment, Beta's face mask has slipped below his nose - but we then immediately see a shot from another camera in which the mask is in place again.
ep 4 -	The one time we see a whole Kroton (as it emerges from the Machine), spot the bulge in the bottom section where the operator's leg is moving.
ep ? -	Keep an ear out for Pat Troughton's tendency to say "Joey" instead of "Jamie, Zoe" ?
ep ? -	When the Doctor and Zoe are being taken into the Krotons, we see Jamie coming to stop them. The strange thing is, we see Jamie starting to run from a standstill, but supposedly he has just being running from somewhere else.

The Seeds of Death:
ep 1,2 -	In episode 2, Fewsham tells Miss Kelly that Osgood killed Locke when he tried to fuse the controls, but back in episode 1, Locke told Radner and Miss Kelly that it was Osgood who died.
ep 2 -	The microphone is out of range when Miss Kelly gives her line about having enough fuel reserves to reach the moon.
ep 3 -	In the storeroom, when Zoe says "I think I heard something", she opens the door to the sight of an Ice Warrior standing right outside the door. But when we cut to a shot from the corridor showing Zoe looking out, the Ice Warrior has magically teleported itself several yards down the corridor and is facing the other way!
ep 4 -	Phipps lifts Zoe up too high to get through the air vent,and she bumps her head.
ep 5 -	When Eldred points to the Weather Control Bureau on a map, notice that it's actually in the opposite corner of the map to the one he's pointing to.
ep ? -	The Doctor's hair goes through remarkable changes in length and thickness throughout the course of the story. An example: He finds out Radner hasn't received the message to make it rain, and comes to the conclusion that Jamie and Zoe have gone to the weather control centre themselves. Radner then says that this was where the Ice Warrior was last seen and the Doctor rushes out. (He's very hirsute at this point). Outside, the Doctor is running fast, probably trying to make up the time lost when he went for his haircut -- as his hair is suddenly an awful lot shorter! Obviously a regenerating hairstyle is one of those mysterious Time Lord gifts.
ep ? -	Watch the scene in the storage room where Jamie is fighting with an Ice Warrior. At some point one of them knocks against the wall, and it wobbles quite distinctly.
ep ? -	Watch for when one of the crew on the Moonbase is attacked by the Ice Warrior. He collapses across the main control console, which wobbles like a piece of cardboard, amazingly enough.
ep ? -	When the Doctor enters the Weather Control Building (which is full of those suds), he and Zoe race down a corridor, then stop and talk for a few seconds. They then start to rush off to find Jamie when Zoe says, "No, this way" and points. Wendy Padbury starts going in that direction but slips on the mess of suds that is all over the floor. She bumps into the Doctor (who is also having balancing problems) almost knocking him over in the process... Finally, they both stagger off the screen. Pure slapstick!
ep ? -	Take a look at one of the Ice Warriors approaching the Weather Control station. There is a head-and-shoulders shot in which several strands of long black hair are sticking out from beneath the back of his helmet... (Though of course, we don't know whether or not Ice Warriors actually do have hair - who knows what they're hiding under that armour?)
ep ? -	Watch carefully for the scene where Zoe's pants are falling down. She's in the background and looks very silly!
ep ? -	During the scene in the space museum when they're building the rocket, you can distinctly hear the sound of a wrench (or some other metal tool) being dropped on the cement floor.
ep ? -	Zoe refers to Slaar by name, though none of the other characters seem to know his name, and never mention it.

The Space Pirates:
ep 2 -	When General Hermack gets coffee for himself, it's obvious that he's pretending -- nothing emerges from the machine!
ep 2 -	When the Doctor, Jamie and Zoe wake up and the Doctor asks "What's that noise?", suddenly there's a totally out-of-place close-up of Zoe looking like she's crying, for no apparent reason!
ep 3,4 -	At the climax to episode 3 (as the Doctor and company fall off a cliff), their screams can be heard for several seconds -- but at the start of episode 4, we can see that they've only fallen a few feet.

The War Games:
ep 2 -	The Doctor is in a tree with Zoe, and he's looking through a mini-telescope at some troop movements. However, when the scene switches back to the Doctor and Zoe, the picture is still cropped into a circle for a brief moment.
ep 7 -	The Doctor tells Zoe and Russell that he is sending them back to the 1917 zone, but they end up in the American Civil War zone instead.
ep 7,8 -	The cliffhanger and reprise don't match - observe the order in which the Doctor, Security Chief and guards file into the SIDRAT in both.
ep ? -	Zoe has supposedly memorised the names of the resistance leaders, yet she doesn't know who the Mexican is.
ep ? -	At one point, Zoe seems to be trying hard to hold her pants up. The story goes that her buckle and zipper broke, but the filming was so far behind schedule that they told her to keep going regardless. What a trooper.