 Chester MorrisHoratio 'Boston Blackie' Black | Horatio 'Boston Blackie' Black |
 Erik RolfDooley Watson | Dooley Watson |
 Jeanne BatesMary Watson | Mary Watson |
 Richard LaneInsp. John Farraday | Insp. John Farraday |
 George E. StoneThe Runt | The Runt |
 Lloyd CorriganArthur Manleder | Arthur Manleder |
 Douglas FowleyNails Blanton (Uncredited) | Nails Blanton (Uncredited) |
 Sid MeltonBenny Hines (Uncredited) | Benny Hines (Uncredited) |
 Ray TealPoliceman Joe (Uncredited) | Policeman Joe (Uncredited) |
 Maude EburneEdna Counihan (Uncredited) | Edna Counihan (Uncredited) |
 Arthur HunnicuttElwood "Tex" Stewart (Uncredited) | Elwood "Tex" Stewart (Uncredited) |
 Cy KendallJumbo Madigan (Uncredited) | Jumbo Madigan (Uncredited) |
| LLarry OlsenJohnny Watson (Uncredited) | Johnny Watson (Uncredited) |
 Pierre WatkinState Governor Rutledge (Uncredited) | State Governor Rutledge (Uncredited) |
 Walter SandeDetective Sergeant Matthews (Uncredited) | Detective Sergeant Matthews (Uncredited) |
| JJack CarrCarpet Man (Uncredited) | Carpet Man (Uncredited) |
 Richard AlexanderCarpet Man (Uncredited) | Carpet Man (Uncredited) |
| GGeorge AndersonWarden J.A. Edwards (Uncredited) | Warden J.A. Edwards (Uncredited) |
 Jessie ArnoldWoman in Hallway (Uncredited) | Woman in Hallway (Uncredited) |
 Trevor BardetteManny Vogel (Uncredited) | Manny Vogel (Uncredited) |
 Eddie BruceSandy (Uncredited) | Sandy (Uncredited) |
| SSally CairnsRichie Adair (Uncredited) | Richie Adair (Uncredited) |
 Eddy ChandlerPoliceman Frank (Uncredited) | Policeman Frank (Uncredited) |
| JJames ConatyParole Board Member (Uncredited) | Parole Board Member (Uncredited) |
 Heinie ConklinPolice Desk Sergeant (Uncredited) | Police Desk Sergeant (Uncredited) |
| MMarie De BeckerMiss Bailey (Uncredited) | Miss Bailey (Uncredited) |
 Sayre DearingReporter at Parole Board Hearing (Uncredited) | Reporter at Parole Board Hearing (Uncredited) |
 Minta DurfeeWoman in Hallway (Uncredited) | Woman in Hallway (Uncredited) |
| BBen ErwayPrison Warden Root (Uncredited) | Prison Warden Root (Uncredited) |
| JJerry FrankGeorge Phillips (Uncredited) | George Phillips (Uncredited) |
