Donald Gray
— James Martin
Ann Wemyss
— Joan Bauer
Mary Newcomb
— Helen Rollins
Ronald Ward
— Michael Waring
Henri De Vries
— Professor Bauer
Alastair Sim
— 'Pop' Lawler
James Carew
— Dr. Rollins
Henry Caine
— Sergeant Cox
Eric Hales
— Carter
Joana Pereira
— Miss Bauer
Arnold Bell
— Leech
Lillian Talbot
— Mrs. Barker