UNIT attempt to track down the Zygon ship while Broton prepares to … The Doctor, Sarah and Harry return to Earth in response to an emergency space-time telegraph from the Brigadier, who asks them to investigate the destruction of a series of North Sea oil rigs. Although two more UNIT stories followed later this season, this was the last appearance of the Brigadier until 1983's Mawdryn Undead. With Tom Baker, Elisabeth Sladen, Ian Marter, John Woodnutt. The Zygon traps the Doctor and Sarah in a decompression chamber while Harry is taken to the aliens' underwater ship. Doctor Who 04 S13E02 Terror of the Zygons Pt 2 - Dailymotion It had been originally produced to conclude season 12 and saw the last regular appearance of Ian Marter as Harry Sullivan and was the first UNIT story since Robot. Originally a six parter entitled The Secret of Loch Ness, it was conden… Directed by Douglas Camfield. Duration: 01:01 With Tom Baker, Elisabeth Sladen, Ian Marter, John Woodnutt. Online multiplayer game Nightfall adds Doctor Who for a limited time! Directed by Douglas Camfield. Harry meets Broton, War Lord of the Zygons. Directed by Douglas Camfield. Terror of the Zygons was the first serial of season 13 of Doctor Who. With Tom Baker, Elisabeth Sladen, Ian Marter, John Woodnutt.