Deathworld (unproduced TV story)
Deathworld was an early proposal by Bob Baker and Dave Martin for Season 10 which would have celebrated the series' tenth anniversary. Elements from Deathworld formed the basis for The Three Doctors.
The short proposal for this story detailed that it would involve the Time Lords in conflict with a Federation of Evil led by a personification of Death. To avert all-out war, the Time Lords manage to convince the Federation to allow them to send the three Doctors into the Federation's Underworld domain. There, the Doctors will do battle against various realisations of Death — including zombies, the Four Horsemen of the Apocalypse, the Hindu goddess Kali, and the cyclops Polyphemus from Greek mythology — with the victor in the contests determining whether the Time Lords or the Federation of Evil will prevail. (DW50Y 3)
Deathworld was adapted into an audio story in The Lost Stories.