Bud Abbott as Bud Alexander

Lou Costello as Lou Francis

Nancy Guild as Helen Gray

Arthur Franz as Tommy Nelson

Adele Jergens as Boots Marsden

Sheldon Leonard as Boots Morgan

William Frawley as Det. Roberts

Gavin Muir as Dr. Philip Gray

Sam Balter as Radio Announcer

John Daheim as Rocky Hanlon

Walter F. Appler as Professor Dugan (uncredited)

Bobby Barber as Sneaky (uncredited)

Howard Banks as Officer (uncredited)

Richard Bartell as Bald Man (uncredited)

Phil Bloom as Fight Spectator (uncredited)

John Breen as Trainer (uncredited)

Milt Bronson as Ring Announcer (uncredited)

Ralph Brooks as Man at Bar (uncredited)

Steve Carruthers as Reporter (uncredited)

Tom Coleman as Dugan Detective School Graduate (uncredited)

Chester Conklin as Counter Man (uncredited)

Bing Conley as Trainer (uncredited)

Russ Conway as Newspaperman (uncredited)

Paul Cristo as Fight Spectator (uncredited)

Frank Dae as Col. Duffie (uncredited)

Roy Darmour as Man (uncredited)

Sayre Dearing as Reporter (uncredited)

Jack Deery as Hospital Visitor (uncredited)

James Dime as Man in Gym (uncredited)

Ralph Dunn as Motorcycle Cop (uncredited)

George Ford as Reporter (uncredited)

Edward Gargan as Milt (uncredited)

Harold Goodwin as Bartender (uncredited)

Dick Gordon as Man (uncredited)

Kit Guard as Fighter on Rowing Machine (uncredited)

Bobby Hale as Graduation Spectator (uncredited)

Chuck Hamilton as Policeman (uncredited)

Stuart Holmes as Fight Spectator (uncredited)

Kenner G. Kemp as Policeman (uncredited)

Johnny Kern as Trainer (uncredited)

Donald Kerr as Fight Spectator (uncredited)

Perc Launders as Cop (uncredited)

George J. Lewis as Torpedo Al (uncredited)

Rory Mallinson as Tough Guy in Bar (uncredited)

Paul Maxey as Dr. Turner (uncredited)

Mathew McCue as Graduation Spectator (uncredited)

Hans Moebus as Restaurant Patron (uncredited)

Ralph Montgomery as Photographer (uncredited)

Mike Morelli as Training Spectator (uncredited)

William H. O'Brien as Fight Spectator (uncredited)

Monty O'Grady as Fight Spectator (uncredited)

Franklin Parker as Photographer (uncredited)

Jack Perrin as Dugan Detective School Graduate (uncredited)

Jack Perry as Rocky's Handler (uncredited)

Victor Romito as Waiter (uncredited)

Clark Ross as Fight Spectator (uncredited)

Syd Saylor as Waiter (uncredited)

Sammy Shack as Fighter (uncredited)

Edith Sheet as Nurse (uncredited)

Jack Shutta as Attendant (uncredited)

Carl Sklover as Lou's Handler (uncredited)

Billy Snyder as Newspaperman (uncredited)

Brick Sullivan as Dugan Detective School Graduate (uncredited)

Frankie Van as Referee (uncredited)

Herb Vigran as Stillwell (uncredited)

Billy Wayne as Rooney - Rocky's Manager (uncredited)