Part OneSeries Episode Number: 418
World Premiere: Sat 3 Jan 1976 - 5:56pm GMT [BBC One] (United Kingdom)
First Broadcast: Thu 17 Apr 1980 - 5:30pm CST [WTTW 11 Chicago]
Running Time: 25 minutes 25 seconds
9.50 Million (UK)
Chart Position: 30 () (UK)
Recorded on Mon 06 Oct 1975 in TC1
The Doctor and Sarah arrive on the planet Karn. There they take shelter in the castle of Dr Solon who is secretly hiding the living brain of the Time Lord criminal, Morbius.