|Edition: || UK (VHS)|
|When: ||August 1991|
|Format: ||1 x VHS|
"Unless the energy loss is stopped, the whole fabric of space time will be destroyed... We are being consumed"
Time itself is in peril! The three Doctors are united against an old arch enemy...
Vital cosmic energy is draining into a black hole and the Timelords [sic] are under siege. The Doctor is their only hope but, trapped in the TARDIS, he's powerless. The only way out is to break the First Law of Time to let the Doctor help himself... literally...
Originally transmitted 30th December 1972 - 20th January 1973, this special tenth anniversary adventure is available for the first time on BBC Video.