Last updated 24 March 2024


Episode 7

Series Episode Number: 264

World Premiere: Sat 14 Mar 1970 - 5:15pm BST [BBC One] (United Kingdom)
First Broadcast: Thu 2 Oct 2014 - 8:00pm EDT [Retro TV]
Running Time: 22 minutes 55 seconds

7.50 Million (UK)

Appreciation Index: 58 (UK)

Chart Position: 54 () (UK)

Recorded on Mon 26 Jan 1970 in Television Centre 8
Archive State: PAL Restor



As the Silurian plague quickly spreads, the Doctor desperately searches for a cure. But the Silurians are aware of the Doctor's efforts and intend to stop him.


Characters hide uncredited
Doctor WhoJon Pertwee
Liz ShawCaroline John
Brigadier Lethbridge-StewartNicholas Courtney
Captain HawkinsPaul Darrow
Corporal NuttingAlan Mason
Young SilurianNigel Johns
Silurian ScientistPat Gorman
Silurian VoicePeter Halliday
SilurianPaul Barton
SilurianSimon Cain
SilurianDave Carter
SilurianJohn Churchill
UNIT SoldierBrian Haughton (uncredited)
ReceptionistSheila Knight (uncredited)
UNIT SoldierMark Johnson (uncredited)
UNIT SoldierAlex Donald (uncredited)
UNIT SoldierDavid Melbourne (uncredited)
TechnicianRonald Gough (uncredited)
TechnicianPeter Holmes (uncredited)
TechnicianRichard King (uncredited)
TechnicianLeonard Kingston (uncredited)
TechnicianKeith Ashley (uncredited)
TechnicianStuart Myers (uncredited)
TechnicianCy Town (uncredited)
TechnicianJoan Harsant (uncredited)
TechnicianCara Stevens (uncredited)