The Sixth Doctor and Peri arrive on the planet Necros where, in a facility called Tranquil Repose presided over by Mr Jobel and his assistant Tasambeker, the wealthy can have their newly-deceased bodies cryogenically frozen until such time as medical science can cure whatever killed them.
The Doctor wishes to pay his last respects to his friend Professor Arthur Stengos, and also to assuage some nagging suspicions about the man's death. His suspicions prove justified, as it turns out that this is just a ruse to lure him into a trap.
The Great Healer masterminding Tranquil Repose is Davros, who is using the organic material in the cryogenic storage units both as the raw material for the synthetic food that is Necros's biggest export and also to create a whole new army of Daleks with which to take control of the universe.
Davros's plans are foiled when Daleks loyal to the Dalek Supreme arrive on Necros and take him prisoner. The Doctor suggests to the planet's inhabitants a new basis for their economy.