Chester Morris

Dr. Carlo Lombardi

Marla English

Andrea Talbott / Elizabeth Wetherby

Tom Conway

Timothy Chappel

Cathy Downs

Dorothy Chappel

Lance Fuller

Dr. Ted Erickson

Ron Randell

Police Lt. Ed James

Frieda Inescort

Mrs. Chappel

Frank Jenks

Plainclothes Sgt. with Lt James

El Brendel

Olaf, the butler

Paul Dubov

Johnny, the barker

William Hudson

Bob, the ex-fiancé

Flo Bert

Marta, the Maid

Jeanne Evans

Mrs. Brown

Kenneth MacDonald

Police Doctor with Prof. Anderson

Jack Mulhall

Lombardi's Lawyer

Edward Earle

Professor Anderson

Bess Flowers

Party Guest

Paul Blaisdell

The She-Creature

Spike

King the Dog