Part FourSeries Episode Number: 385
World Premiere: Sat 18 Jan 1975 - 5:31pm GMT [BBC One] (United Kingdom)
First Broadcast: Fri 29 Feb 1980 - 5:30pm CST [WTTW 11 Chicago]
Running Time: 24 minutes 29 seconds
9.00 Million (UK)Appreciation Index: 51 (UK)
Chart Position: 30 () (UK)
Recorded on Fri 07 Jun 1974 in TC7
The Doctor races to avert a nuclear holocaust. The robot, distraught over killing its creator, takes Sarah hostage and goes on a rampage.