The East Side Kids discover that one of their own, Danny, is torn between staying in school and becoming a boxer, and is getting mixed up with gangsters.
| Actor | Role |
|---|---|
 Leo GorceyMuggs McGinnis | Muggs McGinnis |
 Bobby JordanDanny Breslin | Danny Breslin |
 Huntz HallLimpy | Limpy |
 Warren HullOfficer Tom Brady | Officer Tom Brady |
 Charlotte HenryMary Breslin | Mary Breslin |
 Keye LukeClancy | Clancy |
| BBobby StoneMonk Martin | Monk Martin |
 Donald HainesSkinny, red-haired kid | Skinny, red-haired kid |
 Sunshine Sammy MorrisonScruno | Scruno |
 David GorceyPeeWee | PeeWee |
 Martha WentworthMrs. Brady | Mrs. Brady |
 Jack MulhallCop at Prizefight with the Lieutenant | Cop at Prizefight with the Lieutenant |
| EEddie FosterSlats Morrison | Slats Morrison |
 Dennis MooreDorgan | Dorgan |
| TTony CarsonHenchman Dutch | Henchman Dutch |
| PPat CostelloMuggs' Trainer | Muggs' Trainer |
| DDick RyanPolice Lieutenant | Police Lieutenant |
| BBill CartledgeJohnny Ryan, Muggs' opponent (uncredited) | Johnny Ryan, Muggs' opponent (uncredited) |
 Minerva UrecalHead of Reform School (uncredited) | Head of Reform School (uncredited) |
 Jack ChefeHenchman Nick (uncredited) | Henchman Nick (uncredited) |
| JJack CarrMilkman George (uncredited) | Milkman George (uncredited) |