Prof. Bernard Quatermass

Brian Donlevy

Mrs. Judith Carroon

Margia Dean

Insp. Lomax

Jack Warner

Victor Carroon

Richard Wordsworth

Dr. Gordon Briscoe

David King-Wood

Rosemary "Rosie" Elizabeth Wrigley

Thora Hird

BBC TV producer

Gordon Jackson

Marsh (uncredited)

Maurice Kaufmann

Christie

Harold Lang

Det. Sgt. Best (uncredited)

John Wynn

Blake

Lionel Jeffries

Police Sergeant Questioning Rosie

Sam Kydd

Little Girl (uncredited)

Jane Asher

The Chemist (uncredited)

Toke Townley

BBC Announcer

Frank Phillips

Dr. Ludwig Reichenheim (uncredited)

Stanley van Beers

TV Program Announcer (uncredited)

Donald Gray

Maggie (uncredited)

Margaret Anderson

Maggie's Boyfriend (uncredited)

Eric Corrie

Central Clinic Nurse (uncredited)

Marianne Stone

George - Maggie's Father (uncredited)

Henry B. Longhurst

Crash Site Fire Chief (uncredited)

Ernest Hare

Crash Site Fireman (uncredited)

Michael Godfrey

Photo Lab Technician (uncredited)

John Kerr

Zookeeper (uncredited)

Bartlett Mullins

Zoo Superintendent (uncredited)

Mayne Lynton

Nurse Tucker (uncredited)

Barry Lowe

Mrs. Lomax (uncredited)

Jane Aird

Mother at Zoo (uncredited)

Molly Glessing

TV Show Floor Director (uncredited)

Arthur Gross

Sir Lionel Dean (uncredited)

Basil Dignam

Charles Greene (uncredited)

Gron Davies

Ludwig Reichenheim (uncredited)

Stanley Van Beers

Sergeant Bromley (uncredited)

Arthur Lovegrove

Sound Engineer (uncredited)

James Drake