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