A boxer is killed in the ring, and the only clue is a tune that a man was whistling.
Neil Hamilton
as Bill Devons
Evelyn Venable
as Pauline Ward
Jimmy Wallington
as Nick Nicholls
Barbara Pepper
as Althea Ames
Lucien Littlefield
as Watchman
Lynne Roberts
as Edna Mayberry (as Lynn Roberts)
James Spottswood
as Albert 'Slats' Keefe
Reed Hadley
as Ralph Mortimer
Robert Homans
as Captain Joseph Filsom
William Haade
as Tommy Madison - the Champ
Pat Flaherty
as Ace Cummings
Dan Tobey
as Announcer Dan Tobey
