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