Brian Donlevy
Prof. Bernard Quatermass
Richard Wordsworth
Victor Carroon
David King-Wood
Dr. Gordon Briscoe
Jack Warner
Inspector Lomax
Margia Dean
Judith Carroon
Maurice Kaufmann
Marsh
John Wynn
Detective Sergeant Best
Harold Lang
Christie
Lionel Jeffries
Blake
Thora Hird
Rosie Wrigley
Sam Kydd
Police Sergeant Questioning Rosie
Jane Asher
Little Girl (uncredited)
Toke Townley
The Chemist (uncredited)
Gordon Jackson
BBC TV producer
