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)

John Bleifer

Murdered Orderly (uncredited)

Stanley Blystone

Backstage Cop Who Shoots Gravelle (uncredited)

Myrta Bonillas

Villager in Opera (uncredited)

Raymond Brown

Guard (uncredited)

Jim Farley

Detective (uncredited)

Adolph Faylauer

Opera Spectator (uncredited)

Larry Fisher

Cop (uncredited)

Benson Fong

Opera Supernumerary (uncredited)

J. C. Fowler

Opera Spectator (uncredited)

Otto Fries

Innkeeper (uncredited)

Bud Geary

Cop (uncredited)

Herschel Graham

Villager in Opera (uncredited)

Harrison Greene

Detective (uncredited)

Julia Griffith

Opera Spectator (uncredited)