You'll Find Out

Kay Kyser

Himself

Peter Lorre

Professor Karl Fenninger

Boris Karloff

Judge Spencer Mainwaring

Lugosi Béla

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)