Bud Abbott

Cuthbert Greenway / Dr. Ralph Greenway

Lou Costello

Horatio Prim

Marjorie Reynolds

Melody Allen

Binnie Barnes

Mildred Dean

John Shelton

Sheldon Gage

Gale Sondergaard

Emily

Lynn Baggett

June Prescott

Jess Barker

Thomas Danbury

Ann Gillis

Nora O'Leary

Donald MacBride

Lt. Mason

William Hall

Sgt. Conners

Robert Barrat

Maj. Putnam

Rex Lease

Sgt. Makepeace

Kirk Alyn

Dandy at Party (uncredited)

Harry Brown

Second Sergeant (uncredited)

Wheaton Chambers

Bill - Museum Guard (uncredited)

James Conaty

Party Guest (uncredited)

John Crawford

Dandy at Party (uncredited)

Vernon Downing

Leigh - Traitor (uncredited)

Marjorie Eaton

Bessie - Danbury's Maid (uncredited)

Myron Healey

Dandy at Party (uncredited)

Boyd Irwin

Cranwell - Traitor (uncredited)

Selmer Jackson

Mr. Dibbs - Museum Curator (uncredited)

William H. O'Brien

Danbury Servant (uncredited)