Ellery Queen

Ralph Bellamy

Acting

Nikki Porter

Margaret Lindsay

Acting

Insp. Queen

Charley Grapewin

Acting

Sgt. Velle

James Burke

Acting

Dr. James Rogers

Michael Whalen

Acting

Barbara Braun

Marsha Hunt

Acting

John Braun

Fred Niblo

Directing

Dr. Prouty

Charles Lane

Acting

Lydia Braun

Ann Shoemaker

Acting

Cornelia

Marion Martin

Acting

Rocky Taylor

Douglas Fowley

Acting

Zachary

Morgan Wallace

Acting

Amos

Byron Foulger

Acting

Valerie Norris

Katherine DeMille

Acting

Doctor's Assistant (uncredited)

Peter Bronte

Acting

Desk Sergeant (uncredited)

Jack Cheatham

Acting

Elevator Guard (uncredited)

Arthur Millett

Acting

Ambulance Driver (uncredited)

Frank O'Connor

Acting

Flynn (uncredited)

Lee Phelps

Acting

Rogers' Assistant (uncredited)

Jack Rice

Acting

Elevator Passenger (uncredited) (unconfirmed)

Alan Ladd

Acting