Jon Pertwee

Character: The Doctor

Katy Manning

Character: Jo Grant

Nicholas Courtney

Character: Brigadier Lethbridge-Stewart

John Levene

Character: Sergeant Benton

Richard Franklin

Character: Captain Mike Yates

Stewart Bevan

Character: Cliff Jones

Jerome Willis

Character: Stevens

Tony Adams

Character: Elgin

Ben Howard

Character: Hinks

Mostyn Evans

Character: Dai Evans

Talfryn Thomas

Character: Dave

Roy Evans

Character: Bert

Mitzi McKenzie

Character: Nancy

Ray Handy

Character: Milkman

John Scott Martin

Character: Hughes

John Rolfe

Character: Fell

John Dearth

Character: BOSS (voice)

Richard Beale

Character: Minister of Ecology

Jean Burgess

Character: Cleaner

Brian Justice

Character: Yates' Guard

Terry Walsh

Character: Guard

Roy Skelton

Character: James