Boris Karloff

as Mr. James Lee Wong

Marjorie Reynolds

as Roberta 'Bobbie' Logan

Grant Withers

as Police Capt. Bill Street

Huntley Gordon

as Mr. Davidson

George Lynn

as Capt. Guy Jackson

William Royle

as Capt. Jaime

James Flavin

as Police Sgt. Jerry

Lotus Long

as Princess Lin Hwa

Lee Tung Foo

as Willie

Bessie Loo

as Lilly May

Ernie Stanton

as Bailey

I. Stanford Jolley

as Palisser Hotel Clerk

Jack Kennedy

as Sgt. Brady

Donald Kerr

as Taxi Driver

Wilbur Mack

as The Coroner

Moy Ming

as Aged Tong Member

Bruce Mitchell

as Police Officer at Explosion

Angelo Rossitto

as Mute Dwarf

Guy Usher

as Police Commissioner

Richard Loo

as Tong Chief