Cast
Ralph Bellamy
Ellery Queen
Margaret Lindsay
Nikki Porter
Charley Grapewin
Insp. Queen
James Burke
Sgt. Velle
Michael Whalen
Dr. James Rogers
Charles Lane
Dr. Prouty
Ann Shoemaker
Lydia Braun
Marion Martin
Cornelia
Marsha Hunt
Barbara Braun
Byron Foulger
Amos
Jack Cheatham
Desk Sergeant (uncredited)
Frank O'Connor
Ambulance Driver (uncredited)
Fred Niblo
John Braun
Katherine DeMille
Valerie Norris
Douglas Fowley
Rocky Taylor
Morgan Wallace
Zachary
Lee Phelps
Flynn (uncredited)
Jack Rice
Rogers' Assistant (uncredited)
Alan Ladd
Elevator Passenger (uncredited) (unconfirmed)