Top Cast
Frank Buck
Frank Hardy
Sasha Siemel
Tiger Van Dorn
Reginald Denny
Ralph Marshall
Esther Ralston
Valerie Shields
Charlotte Henry
Dorothy Elliott
William Bakewell
Tom Banning
Clarence Muse
Lightning
Willie Fung
Chiang-Houseboy
LeRoy Mason
Jim Murphy
Matthew Betz
Inspector Starrett
Richard Tucker
Robert Banning
Duncan Renaldo
Armand Roget
Fred Kohler Jr.
John Charles
Sherwood Bailey
Paul Marshall
Harry 'Snub' Pollard
Campbell
George Rosener
Professor
Gertrude Sutton
Mrs. Maitland
John St. Polis
Chandler Elliott
John Davidson
Doctor Coleman
Milburn Morante
Singapore Joe
Dirk Thane
Joe Nolan
Robert Warwick
Angus MacLeod
Dahlam Ali
Hardy's Assistant
Jim Corey
Henchman
Paul Ellis
Greenway
Henry Hale
Jackson
Harry Harvey
Roget Clerk #1
Reed Howes
Sailor
Jack Ingram
Undercover Detective at Dive
Tom London
Detective Interrogating Pete
Merrill McCormick
Peters
Blackie Whiteford
Henchman
Roger Williams
Henchman