Leo Gorcey
— Terence Aloysius 'Slip' Mahoney
Huntz Hall
— Horace Debussy 'Sach' Jones
Bobby Jordan
— Bobby
William Benedict
— Whitey
David Gorcey
— Chuck
Teala Loring
— Cathy Smith
Sheldon Leonard
— Ace Deuce Baker
Daun Kennedy
— Maizie (as Dawn Kennedy)
James Burke
— Detective O'Malley
Vince Barnett
— Street Cleaner
William 'Wee Willie' Davis
— Moose McCall (as Wee Willie Davis)
William Ruhl
— Henchman Spike
Emmett Vogan
— Mr. Johnson
Bernard Gorcey
— Louie Dumbrowsky
Milton Parsons
— Professor Schnackenberger
Lester Dorr
— Feather-Fingers
William Newell
— Detective Dugan
Eddie Dunn
— Police Officer O'Hara