Calificación
Reparto

Brian Donlevy
Prof. Bernard Quatermass

Richard Wordsworth
Victor Carroon

David King-Wood
Dr. Gordon Briscoe

Jack Warner
Inspector Lomax

Margia Dean
Judith Carroon

Harold Lang
Christie

Lionel Jeffries
Blake

Thora Hird
Rosie Wrigley

Gordon Jackson
BBC TV producer

Sam Kydd
Police Sergeant Questioning Rosie

Maurice Kaufmann
Marsh (uncredited)

John Wynn
Detective Sergeant Best (uncredited)

Jane Asher
Little Girl (uncredited)

Toke Townley
The Chemist (uncredited)

Margaret Anderson
Maggie (uncredited)

Eric Corrie
Maggie's Boyfriend (uncredited)