Jack Watling
— Mike Brewster
Carole Lesley
— Susan
Renée Houston
— Mrs. Gray
John Slater
— Sid Johnson
Colin Gordon
— Mitchell
Libby Morris
— Trixie
Cardew Robinson
— Micki
June Cunningham
— Rosie
Ronald Adam
— Judge
Ernest Clark
— Colonel Drew
John Salew
— Mr. Monkton
Vic Wise
— Spider
Hugh Morton
— Grant
Julian Orchard
— Walker
Tony Thawnton
— Costume Designer
Larry Taylor
— Large Man
Ruth Lee
— Receptionist
Johnny Vyvyan
— Big Louis
Jeanne Moody
— Barbara Drew
Marne Maitland
— Eastern Gentleman
Gertan Klauber
— Joe
Alf Dean
— Enormous Man
Frank Forsyth
— Barman
Geoffrey Denton
— Counsel
John Watson
— 1st Inventor
Diana Chesney
— Dowager (uncredited)
Walter Henry
— Undercover Detective (uncredited)
Lance Percival
— Stage Prompter (uncredited)