All Cast
Brian Donlevy
Prof. Bernard Quatermass
John Longden
Chief Inspector Lomax
William Franklyn
Dr. Tom Brand
Bryan Forbes
Marsh
Charles Lloyd Pack
Work Camp Manager Dawson
Tom Chatto
Vincent Broadhead, M.P.
John Van Eyssen
The Plant Tour Guide
Sid James
Jimmy Hall
Percy Herbert
Paddy Gorman
Michael Ripper
Ernie the Bartender
John Rae
E. J. Macleod
Philipp Baird
Lab Assistant
Betty Impey
Kelly
Joyce Adams
Woman Member of Parliament
Edwin Richfield
Peterson
Vera Day
Sheila
Marianne Stone
Miss Beal
Jane Aird
Mrs. McLeod
Michael Balfour
Harry
John Stuart
The Police Commissioner
John Fabian
Intern
George Merritt
Super