Part Three
Series Episode Number: 404World Premiere: Sat 13 Sep 1975 - 5:46pm BST [BBC One] (United Kingdom)
First Broadcast: Thu 27 Mar 1980 - 5:30pm CST [WTTW 11 Chicago]
Running Time: 24 minutes 9 seconds
8.20 Million (UK)
Appreciation Index: 54 (UK)Chart Position: 32 () (UK)
Recorded on Tue 22 Apr 1975 in TC4 at these locations
BBC Genome Project: see entry
The Doctor and Sarah find their way into the Zygon spaceship at the bottom of Loch Ness while the Brigadier prepares to force it to the surface with depth charges.