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

John Van Eyssen

The Plant Tour Guide

Sidney James

Jimmy Hall

Percy Herbert

Paddy Gorman

Michael Ripper

Ernie the Bartender

Edwin Richfield

Peterson

Vera Day

Sheila

Marianne Stone

Miss Beal

Michael Balfour

Harry

John Stuart

The Police Commissioner

John Fabian

Intern

George Merritt

Super