You'll Find Out

Kay Kyser

— Himself

Peter Lorre

— Professor Karl Fenninger

Boris Karloff

— Judge Spencer Mainwaring

Béla Lugosi

— Prince Saliano

Helen Parrish

— Janis Bellacrest

Dennis O'Keefe

— Chuck Deems

Alma Kruger

— Aunt Margo Bellacrest

Joseph Eggenton

— Jurgen

Ginny Simms

— Herself

Harry Babbitt

— Himself

M.A. Bogue

— Ish Kabibble

Sully Mason

— Himself

Mary Bovard

— Mary (uncredited)

Jeff Corey

— Mr. Corey (uncredited)

Louise Currie

— Marion (uncredited)

Bess Flowers

— Lady In Taxi (uncredited)

Jeanne Houser

— Jean (uncredited)

Richard Kipling

— Script Man (uncredited)

Eleanor Lawson

— Ms. Gaby Lawson (uncredited)

Larry McGrath

— Apartment Complainer (uncredited)

Frank Mills

— Cabbie (uncredited)

Mimi Montaye

— Mimi (uncredited)

Dorothy Moore

— Penny (uncredited)

Leonard Mudie

— Real Karl Fenninger (uncredited)

Joseph North

— Servant (uncredited)

Frank O'Connor

— Apartment Responder (uncredited)

Beulah Parkington

— Mother (uncredited)

Jane Patten

— Jane (uncredited)

Eugenia Rafee

— French Maid (uncredited)

William Telaak

— Mac (uncredited)