Directed by: Michael Hayes
Produced by: Graham Williams
Written by: Dave Martin
The last stretch of the quest for the Key to Time brings the Doctor and Romana to the planet Atrios in the last days of a nuclear war with its neighboring planet Zeos. The Atrian ruler, Princess Astra, presses for peace, but the Marshal insists that his forces can win the war. Those near the Marshal fear that his judgment is suffering from the strain of command. He has taken to making most of his decisions following meditations before a strange black mirror. The Princess has disappeared, and the Marshal now rules unopposed. Have the Doctor and Romana arrived too late to complete their mission before Atrios is destroyed? When the Doctor learns that no living Atrian has ever met a Zeon, he proposes to travel to Zeos to negotiate for peace and the return of Princess Astra, who seems to be linked in some way to the sixth segment. He finds the planet deserted. There are no living Zeons, but they left the computer running, and it's programmed for Mutual Assured Destruction.
Audio Commentary 1 by actors Mary Tamm (Romana) and John Woodvine (The Marshal) and director Michael Hayes ● Audio Commentary 2 by actors Tom Baker (The Doctor), Mary Tamm and John Leeson (K-9) ● Production Note Option ● DVD-ROM PC / Mac feature: The Doctor Who Annual 1979, Radio Times billings● Defining Shadows "Making Of" documentary featuring writers Bob Baker and Dave Martin, designer Richard McManan-Smith, and actors Lalla Ward (Astra), David Harries (Shapp) and Barry Jackson (Drax) (15 mins) ● Directing Who Director Michael Hayes talks about his directing career (8 mins) ● Rogue Time Lords Potted history of errant Gallifreyans (13 mins) ● Pebble Mill at One 1978 Tom Baker interview (8 mins) / Interview with Dick Mills and Brian Hodgson of the Radiophonic Workshop (4 mins) ● The New Sound of Music Dick Mills on series sound effects (1 min) ● Merry Christmas Doctor Who Sketch for 1978 BBC Christmas tape (1 min) ● Late Night Story Tom Baker reads five spine-chilling stories from an unbroadcast 1978 series (69 mins) ● Alternative/Extended Scene (3 mins) ● Continuities (3 mins) ● Photo Gallery (5 mins)