Peter Cushing as Doctor Who

Bernard Cribbins as Tom Campbell

Ray Brooks as David

Andrew Keir as Wyler

Roberta Tovey as Susan

Jill Curzon as Louise

Godfrey Quigley as Dortmun

Roger Avon as Wells

Keith Marsh as Conway

Philip Madoc as Brockley

Eddie Powell as Thompson

Steve Peters as Lead Roboman

Geoffrey Cheshire as Roboman

Eileen Way as Old Woman

Sheila Steafel as Young Woman