Doctor Who - Season 21 - Eps 16: Planet of Fire (4)
While the Master, victim of his own attempt to improve his TCE weapon, seeks restoration through Sarn's numismaton gas, the truth of Turlough's past comes out at last, though to guarantee the safety of his brother and the Sarn people, Turlough must consider a great personal sacrifice.
About Doctor Who

Title: Doctor Who
First Air Date: 1963-11-23
Last Air Date: 1989-12-06
Status: Ended
Rating: 7.869/10 (from 666 votes)
Language: EN
Seasons: 27
Total Episodes: 694
Network: BBC One BBC Television
Genres: Drama, Action & Adventure, Sci-Fi & Fantasy
Production Companies: BBC
Synopsis
The adventures of The Doctor, a time-traveling humanoid alien known as a Time Lord. He explores the universe in his TARDIS, a sentient time-traveling spaceship. Its exterior appears as a blue British police box, which was a common sight in Britain in 1963 when the series first aired. Along with a succession of companions, The Doctor faces a variety of foes while working to save civilizations, help ordinary people, and right many wrongs.
Cast

Sylvester McCoy
The Doctor

Sophie Aldred
Ace