นักแสดง
Nedda Harrigan
Mme. Lucretia Borelli
Charlotte Henry
Mlle. Kitty
Jim Farley
Detective (uncredited)
Benson Fong
Opera Supernumerary (uncredited)
Otto Fries
Innkeeper (uncredited)
Frank Conroy
Mr. Whitely
William Demarest
Sergeant Kelly
Margaret Irving
Mme. Lilli Rochelle
Bud Geary
Cop (uncredited)
Tom McGuire
Pop Morris - Stage Doorman
Boris Karloff
Gravelle
Guy Usher
Inspector Regan
Gregory Gaye
Enrico Borelli
John Bleifer
Murdered Orderly (uncredited)
Frank Fanning
Cop (uncredited)
Keye Luke
Lee Chan
Thomas Beck
Phil Childers
Marc Lawrence
Undetermined Minor Role (uncredited) (unconfirmed)
William Bailey
Detective (uncredited)
Warner Oland
Charlie Chan
Maurice Cass
Mr. Arnold
Joan Woodbury
Dancer in Opera (uncredited)
Stanley Blystone
Backstage Cop Who Shoots Gravelle (uncredited)
Adolph Faylauer
Opera Spectator (uncredited)