Andrew Keir

Prof. Bernard Quatermass

James Donald

Dr. Mathew Roney

Barbara Shelley

Barbara Judd

Julian Glover

Colonel Breen

Bryan Marshall

Captain Potter

Duncan Lamont

Sladden

Peter Copley

Howell

Edwin Richfield

Minister

Grant Taylor

Police Sergeant Ellis

Noel Howlett

Abbey Librarian

Thomas Heathcote

Vicar

Robert Morris

Jerry Watson

Bee Duffell

Miss Dobson

Sheila Steafel

Journalist

Hugh Morton

Elderly Journalist

Hugh Manning

Pub Customer

June Ellis

Blonde

Keith Marsh

Johnson

James Culliford

Corporal Gibson

Roger Avon

Electrician

Brian Peck

Technical Officer

Gareth Thomas

Workman (uncredited)

Michael Poole

Older Workman (uncredited)