An archaeological expedition finds a strange artefact, which is in fact an alien beacon. Thinking it might be valuable an Earth girl takes it to sell, and jumps into a lake to swim to shore.
She runs into trouble whilst in the lake and is rescued by Turlough, who takes her on board the TARDIS. The Master manages to reassert control over Kamelion, and commands it to take the TARDIS to him on the planet Sarn.
The Master had a small accident with his tissue compression eliminator and has himself become shrunk. He plans to use the planet's revitalising numismaton gas to restore his size.
Turlough discovers that the people of Trion are, or are descendants of, Trion prisoners from a crashed prison ship. Turlough is also one of these prisoners, although he was exiled to Earth with a guardian. On Trion he discovers his long lost brother.
The Master becomes trapped by the numismaton gas as it turns to flame, and is believed to be destroyed. Meanwhile the Trions have extended amnesty to all prisoners, and he leaves for his home world. At Kamelion's request, the Doctor destorys the robot, and leaves with his new companion Peri.
Regular castVislor Turlough: Mark Strickson; Peri Brown: Nicola Bryant;
Guest castThe Master: Anthony Ainley; Voice of Kamelion: Gerald Flood; Chief Elder Timanov: Peter Wyngarde; Sorasta: Barbara Shelley; Amyand: James Bate; Professor Howard Foster: Dallas Adams; Malkon: Edward Highmore; Roskal: Jonathon Caplan; Lookout: Simon Sutton (1-2); Curt: Michael Bangerter (1); Zuko: Max Arthur (2); Lomand: John Alkin (4);
Uncredited cast: Kamelion: Anthony Ainley, Dallas Adams; Boatmen: Miguel Ange Lopez (1), Severino Reye Perdoni (1); Customers at Cafe: Mrs. Bangerter and two children (1); Passersby: (all 1) Enrique Ramiles Lubgauwa, Migua Aoyes Perdoma, Carmelo de Leon Thursado, Dominez Hermandez Tornedo; Trion: Ray Knight (4); Guards: Steven Arnely, Robin Bond, Derek Hunt, David Rogue; Citizens: Andy Andreas, Paul Barton, Barbara Burnell, Ian Marshall Fisher, Jill Goldstone, Rosalind Kendal, Penny Lamberth, Valero Martinez, Stewart Myers, David Payne, Jenny Piper, Brychen Powell, Mary Rennie, Bob Smythe;
|BBC 1||615||Part One||Thu 23 February 1984||6:40 pm - 7:05 pm||7.4M||71st|
|BBC 1||616||Part Two||Fri 24 February 1984||6:40 pm - 7:05 pm||6.1M||102nd|
|BBC 1||617||Part Three||Thu 1 March 1984||6:40 pm - 7:05 pm||7.4M||67th|
|BBC 1||618||Part Four||Fri 2 March 1984||6:40 pm - 7:05 pm||7.0M||74th|
All locations are in Lanzarote, Spain; Fire Mountain, Ridge, Asphalt Triangle, Cave of Doves, Valley of Tranquility; Guide Cave, Steep Hill, High area near Camel Path all at Islote de Hilario, Montarias del Fuego; Mirador del Rio (high observation point); Papagayo Beach and bay; Quay and cafe at Orzola; Volcano Mouth, Yellow Area, Los Hornitos - all at Islote de Hilario, Montarias del Fuego;
Television Centre Studio 1; Television Centre Studio 6;
Bloopers and mistakes
Peri says "Elton John" with an English accent, even though she's supposed to be American.
Watch how the question marks on the Doctor's braces keep changing the way they face, depending on whether Peter Davison is appearing in the studio or on location.
Episode 1: You see the mountains move against the desert floor when the Doctor is walking on the surface of Sarn.
Episode 4: When the Comparator is removed from the Doctor's TARDIS, it is immobilised - but when the Doctor removes the Comparator from the Master's TARDIS, Kamelion is still able to move it into the flame jet.
Notes and trivia
Mark Strickson leaves at the end of the story; in the process we find out about Turlough's background and learn that his first name is Vislor.
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