You'll Find Out

Kay Kyser Himself

Peter Lorre Professor Karl Fenninger

Boris Karloff Judge Spencer Mainwaring

Bela 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)