Um Invento Engenhoso

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