Time-Flight is the seventh and final serial of the 19th season of the British science fiction television series Doctor Who, which was first broadcast in four twice-weekly parts on BBC1 from 22 to 30 March 1982.
The Fifth Doctor, Nyssa, and Tegan, still mourning the loss of their former companion Adric, arrive at Heathrow and learn from Department C19 that one of their Concordes mysteriously vanished just before landing.
The crew and passengers of the missing Concorde believe they are at Heathrow but are enslaved to work under guard of Plasmatons, humanoid blobs of protein held together by the psychokinetic field.
One passenger, Professor Hayter, has seen through the illusion, and lets the Doctor know that they have been forced to work by the mystic Kalid to break into a central chamber at a nearby Citadel.
As the Doctor sets off to see Kalid, Stapley and Hayter attempt to break the other humans free of the illusion, while Nyssa, with her empathic abilities, is able to enter the central chamber freely, along with Tegan, to find the power source controlling the psychokinetic field.
The Master explains that he had been trapped in Earth's past after their last encounter, his own TARDIS damaged, and believed that he could repair it by acquiring the power source in the Citadel; he created the time corridor to obtain human slaves to help break the chamber open.
The Doctor proposes a truce, providing the spare parts including a temporal limiter, to repair the Master's TARDIS in exchange for dropping the psychokinetic field.
[4] Although his character had been killed in the previous story, Matthew Waterhouse's contract extended into the filming of Time-Flight, which is the reason for Adric's illusory appearance in Part Two.