"While visiting the circus with his family, Charlie is recruited by the big top's co-owner to investigate threatening letters that he's received."
Warner Oland
as Charlie Chan
Keye Luke
as Lee Chan
John McGuire
as Hal Blake
Shirley Deane
as Louise Norman
Francis Ford
as John Gaines
J. Carrol Naish
as Tom Holt
Paul Stanton
as Joe Kinney
Boothe Howard
as Dan Farrell
Drue Leyton
as Nellie Farrell
Wade Boteler
as Lt. Macy
Shia Jung
as Su Toy
George Brasno
as Colonel Tim
Olive Brasno
as Lady Tiny
Maxine Reiner
as Marie Norman
Franklyn Farnum
as Mike - Ticket Taker
Harry Lachman
Director
Earl Derr Biggers
Characters
Robert Ellis
Writer
John Stone
Associate Producer
Helen Logan
Screenplay
Daniel B. Clark
Director of Photography
Duncan Cramer
Art Direction
William Eckhardt
Assistant Director
Alex Troffey
Editor
William Lambert
Costume Supervisor
Arthur von Kirbach
Sound
Samuel Kaylin
Music Director