As novice detectives, Bud and Lou come face to face with the Invisible Man.
as Bud Alexander
as Lou Francis
as Helen Gray
as Tommy Nelson
as Boots Marsden
as Boots Morgan
as Det. Roberts
as Dr. Philip Gray
as Radio Announcer
as Rocky Hanlon
as Professor Dugan (uncredited)
as Sneaky (uncredited)
as Officer (uncredited)
as Bald Man (uncredited)
as Fight Spectator (uncredited)
as Trainer (uncredited)
as Ring Announcer (uncredited)
as Man at Bar (uncredited)
as Reporter (uncredited)
as Dugan Detective School Graduate (uncredited)
as Counter Man (uncredited)
as Trainer (uncredited)
as Newspaperman (uncredited)
as Fight Spectator (uncredited)
as Col. Duffie (uncredited)
as Man (uncredited)
as Reporter (uncredited)
as Hospital Visitor (uncredited)
as Man in Gym (uncredited)
as Motorcycle Cop (uncredited)
as Reporter (uncredited)
as Milt (uncredited)
as Bartender (uncredited)
as Man (uncredited)
as Fighter on Rowing Machine (uncredited)
as Graduation Spectator (uncredited)
as Policeman (uncredited)
as Fight Spectator (uncredited)
as Policeman (uncredited)
as Trainer (uncredited)
as Fight Spectator (uncredited)
as Cop (uncredited)
as Torpedo Al (uncredited)
as Tough Guy in Bar (uncredited)
as Dr. Turner (uncredited)
as Graduation Spectator (uncredited)
as Restaurant Patron (uncredited)
as Photographer (uncredited)
as Training Spectator (uncredited)
as Fight Spectator (uncredited)
as Fight Spectator (uncredited)
as Photographer (uncredited)
as Dugan Detective School Graduate (uncredited)
as Rocky's Handler (uncredited)
as Waiter (uncredited)
as Fight Spectator (uncredited)
as Waiter (uncredited)
as Fighter (uncredited)
as Nurse (uncredited)
as Attendant (uncredited)
as Lou's Handler (uncredited)
as Newspaperman (uncredited)
as Dugan Detective School Graduate (uncredited)
as Referee (uncredited)
as Stillwell (uncredited)
as Rooney - Rocky's Manager (uncredited)
