Last updated 24 March 2024


Episode 4

Series Episode Number: 148

World Premiere: Sat 4 Feb 1967 - 5:50pm GMT [BBC One] (United Kingdom)
Running Time: 23 minutes 20 seconds

7.00 Million (UK)

Appreciation Index: 47 (UK)

Chart Position: 65 () (UK)

Recorded on Fri 28 Jan 1966 in Riverside 1
Archive State: Missing



As Zaroff's insane scheme to destroy the world nears completion, the Doctor plans to break down the sea wall and flood Atlantis.


Characters hide uncredited
Dr. WhoPatrick Troughton
ZaroffJoseph Furst
ThousNoel Johnson
BenMichael Craze
JackoPaul Anil
AraCatherine Howe
SeanP G Stephens
OverseerGraham Ashley
Zaroff's guardTony Handy
PollyAnneke Wills
JamieFrazer Hines
DamonColin Jeavons
OverseerRalph Watson
Damon's assistantGerald Taylor
Fish VoiceRalph Watson
Half-Fish Person (flying)Tony Starr (uncredited)
Atlantean RefugeePhilip Joste (uncredited)
Atlantean RefugeeRobin Scott (uncredited)
Atlantean RefugeeRoyston Farrell (uncredited)
Refugee PriestJimmy Mac (uncredited)
Half Fish PersonAlex Donald (uncredited)
Atlantean GuardMichael Earl (uncredited)
Atlantean ChildGary O'Brien (uncredited)
Atlantean ChildEdmond O'Dwyer (uncredited)
Atlantean RefugeeMarguerite Young (uncredited)
Atlantean RefugeeMary Wheeler (uncredited)
Half Fish PersonPerin Lewis (uncredited)
Fish PersonCathy Ash (uncredited)
Fish PersonJudy Nicholls (uncredited)