Anna May Wong as Dr. Mary Ling

Akim Tamiroff as Frank Baturin

J. Carrol Naish as The Professor

Sidney Toler as Dr. Chang Ling

Philip Ahn as Robert 'Bob' Li

Anthony Quinn as Mike Gordon

Bernadene Hayes as Dolly Warren

Roscoe Karns as Rip Harrigan

Ray Mayer as Potatoes

Richard Denning as Jeff, Protective Association Henchman

Archie Twitchell as Interne

Eddie Marr as Bert, Fight Trainer

George Anderson as Detective

Charles B. Wood as 1st Gangster

George Magrill as 2nd Gangster

Charles Trowbridge as Dr. Jones

Lily King as Chinese Woman

Chester Gan as Mr. Foo

Pat West as Announcer at Fight

Guy Usher as Investigator

Sam Ash as Barber (uncredited)

Marie Burton as Nightclub Girl (uncredited)

Dolores Casey as Nightclub Girl (uncredited)

Ethel Clayton as Nightclub Patron (uncredited)

Wong Chung as Chinese Man (uncredited)

Sheila Darcy as Nightclub Girl (uncredited)

Dorothy Dayton as Nightclub Girl (uncredited)

Paula DeCardo as Dancer (uncredited)

Raoul Freeman as Detective (uncredited)

Norah Gale as Nightclub Girl (uncredited)

George Golden as Nightclub Patron (uncredited)

Harriette Haddon as Dancer (uncredited)

Robert Homans as Detective (uncredited)

Gwen Kenyon as Fight Spectator (uncredited)

Judith King as Nightclub Girl (uncredited)

Charles Lee as Tommy Wu (uncredited)

Grace Lem as Chinese Woman (uncredited)

Joyce Mathews as Nightclub Girl (uncredited)

Larry McGrath as Henchman (uncredited)

Ivan Miller as Politician (uncredited)

Moy Ming as Businessman (uncredited)

Helaine Moler as Nightclub Woman (uncredited)

Alexander Pollard as Heath, Baturin's Butler (uncredited)

Cyril Ring as Fight Spectator (uncredited)

Ben Taggart as Henchman (uncredited)

Jimmy Vaughn as Slugger Grady (uncredited)

Luana Walters as Nightclub Girl (uncredited)

Pierre Watkin as Dist. Atty. Philips (uncredited)

Dorothy White as Nightclub Girl (uncredited)

Gloria Williams as Nightclub Girl (uncredited)

Florence Wix as Nightclub Patron (uncredited)