Directed by: Norman Stewart
Produced by: Graham Williams
Written by: Robert Holmes
The search for the fifth segment of the Key to Time brings the Doctor and Romana to the swampy terrain of the third moon of the planet Delta Magna. Almost immediately, they become separated. The Doctor draws fire when he is mistaken for Rohm-Dutt, a notorious gunrunner wanted for supplying firearms to the Swampies, an aboriginal people who were displaced to the marshy moon when human colonists took possession of Delta Magna. A small team from Delta Magna are now developing a refinery in the Swampies' promised territory, but the Swampies are confident that, properly armed, they can drive the humans away. Meanwhile, Romana has been captured by the Swampies and prepared as a sacrificial offering to their god, the mighty Kroll. Thwarting the sacrifice (in which the god was nothing more than a Swampie priest in fancy dress), the Doctor and Romana have incurred the wrath of Ranquin, a fanatical high priest to Kroll. Legendary or not, something is stirring beneath the swamp floor and, if the refinery's instrument readings are correct, it measures five miles across!
Audio Commentary by actors Tom Baker (The Doctor) and John Leeson (Dugeen) ● Variations Location visit from BBC Archive (6 mins) ● In Studio A glimpse into the studio recording of the story (11 mins) ● There's Something About Mary Mary Tamm looks back at her season as Romana (9 mins) ● Philip Madoc - A Villain for All Seasons Retrospective of actor Philip Madoc's numerous roles in Doctor Who (9 mins) ● Continuities (3 mins) ● Photo Gallery (5 mins) ● Production Note Option ● DVD-ROM PC / Mac feature Radio Times billings.