Episode Four
Series Episode Number: 315World Premiere: Sat 18 Mar 1972 - 5:50pm GMT [BBC One] (United Kingdom)
First Broadcast: Thu 20 Nov 1975 - 6:30pm CST [WTTW 11 Chicago]
Running Time: 24 minutes 21 seconds
7.80 Million (UK)
Chart Position: 40 () (UK)
Recorded on Tue 30 Nov 1971 in TC8
Archive State: PAL 2 VT
The Doctor attempts to persuade Captain Hart of the danger that the Master represents. Eager to make contact with the Sea Devils, the Doctor journeys deep into the ocean.
Home Region: