A boxer is killed in the ring, and the only clue is a tune that a man was whistling.
| Actor | Role |
|---|---|
 Neil HamiltonBill Devons | Bill Devons |
 Evelyn VenablePauline Ward | Pauline Ward |
 Jimmy WallingtonNick Nicholls | Nick Nicholls |
 Barbara PepperAlthea Ames | Althea Ames |
 Lucien LittlefieldWatchman | Watchman |
 Lynne RobertsEdna Mayberry (as Lynn Roberts) | Edna Mayberry (as Lynn Roberts) |
| JJames SpottswoodAlbert 'Slats' Keefe | Albert 'Slats' Keefe |
 Reed HadleyRalph Mortimer | Ralph Mortimer |
 Robert HomansCaptain Joseph Filsom | Captain Joseph Filsom |
 William HaadeTommy Madison - the Champ | Tommy Madison - the Champ |
| PPat FlahertyAce Cummings | Ace Cummings |
| DDan TobeyAnnouncer Dan Tobey | Announcer Dan Tobey |
| AAl BayneMax | Max |
 Smiley BurnetteSmiley Burnette | Smiley Burnette |
 Charles WilliamsJake | Jake |
 Al BainMax (as Al Bayne) | Max (as Al Bayne) |