Robert Beatty
Maj. Sam Seagram
Muriel Pavlow
Caroline Cartier
Hartley Power
General Adams (uncredited)
James Donald
Michael Heathley
Noel Willman
Dr. Dennis Bord
Herbert Lom
Dr. Alex Leon
Maurice Denham
Prof. Carrington
Walter Fitzgerald
Sir Charles Craddock
Phyllis Calvert
Lydia Heathley
Stanley Maxted
Prof. Adams
Marianne Stone
Maisie
Marjorie Fielding
Michael's Mother
Cyril Chamberlain
Inspector Carter
Philip Ray
Sentry (uncredited)
Herbert Lomas
George Jackson
Patric Doonan
Brian Jackson
Johnnie Schofield
Jim Barnes (uncredited)