The Doctor finally manages to return Tegan to Heathrow Airport, where he gets involved in the mysterious disappearance of a Concorde. With the TARDIS on board the Doctor and his companions travel on a second Concorde, which also disappears.
The Concordes have been taken back through time by Kalid, alias the Master. The Master plans to gain control of the Xeraphin. The Master's interference has caused the Xeraphin to become split into two parts - good and evil. Whilst the evil side assists the Master, the good side helps the Doctor.
The Doctor fixes the Master's TARDIS so that it is sent back to the Xeraphins' home planet, which will serve as the Master's new prison. Whilst Tegan is looking around Heathrow the TARDIS departs...
- Nyssa: Sarah Sutton
- Tegan Jovanka: Janet Fielding
- Kalid/The Master: Anthony Ainley (credited to Leon Ny Taiy for 1)
- Captain Stapley: Richard Easton
- Flight Engineer Roger Scobie: Keith Drinkel
- First Officer Andrew Bilton: Michael Cashman
- Angela Clifford: Judith Byfield
- Clive Horton: Peter Dahlsen (1)
- Sheard: Brian McDermott (1)
- Captain Urquhart: John Flint (1)
- Jim Andrews: Peter Cellier (1)
- Professor Hayter: Nigel Stock (2-4)
- Adric: Matthew Waterhouse (2)
- Anithon: Hugh Hayes (3-4)
- Zarak: Andre Winterton (3-4)
- Dave Culshaw: Barney Lawrence (1)
- Security Man: Tommy Winward (1)
- Flight Engineer: Richard Bonehill (1)
- Melkur: Graham Cole (1)
- Terileptil: Chris Bradshaw (2)
- Puppeteer: Richard Gregory (2)
- Tannoy Voice: Judith Byfield (1)
- Plasmatons: Steve Fideli, Martin Grant, Chris Holmes, Graham Jarvis, Mykel Mills, Nigel Tisdall
- Plasmaton Voice: Andre Winterton
|BBC 1||576. Part One||Tuesday, March 23, 1982 6:55 PM - 7:20 PM||10.1M|
|BBC 1||577. Part Two||Wednesday, March 24, 1982 7:05 PM - 7:30 PM||8.5M|
|BBC 1||578. Part Three||Tuesday, March 30, 1982 6:55 PM - 7:20 PM||9.1M|
|BBC 1||579. Part Four||Wednesday, March 31, 1982 7:05 PM - 7:30 PM||8.3M|
- Television Centre Studio 8
- Heathrow Airport, Middlesex
Episode 1 : Stapley and Nyssa see the Plasmatons materialise behind the Doctor before they actually appear.
Episode 3 : In the scene where Nyssa is about to be absorbed by the Xeraphin into their casket, she's standing in front and it is glowing in a beam of pale light. While she's standing there shouting, a human hand briefly emerges from the sarcophagus, and then falls back down. Presumably, this was the hand of one of the actors who would later play an emerging Xerophin.
Episode 4 : When Captain Stapley's Concorde finally manages to take off from 140,000,000 B.C., we see hazy stock footage of an airborne plane imposed over the prehistoric set. While the plane is lifting off, a crow flies across the screen from right to left. Now, while crows are quite common and friendly in 1983, were they really that ubiquitous in prehistoric times?