Basil Rathbone
— Dr. George Sebastian / Dr. Langamann
Ellen Drew
— Linda Booth
John Howard
— Gil Sawyer
Barbara Jo Allen
— Louise Watkins (as Barbara Allen [Vera Vague])
Ralph Morgan
— Dr. Charles Downer
Martin Kosleck
— Maurice Gretz
Kitty Kelly
— Winnie
Hugh O'Connell
— Lawrence Watkins
Henry Victor
— Furber (Uncredited)
Wanda McKay
— Girl at Charity Bazaar (Uncredited)
James Seay
— Intern (Uncredited)
William Benedict
— Mickey Barnes (Uncredited)
George Chandler
— Elevator Operator (Uncredited)
Edward Earle
— Librarian (Uncredited)
Chuck Hamilton
— Police Officer at Train Station (Uncredited)
Harry Hayden
— Ticket Clerk (Uncredited)
Douglas Kennedy
— Hotel Clerk (Uncredited)
John Laing
— Intern (Uncredited)
Charles McAvoy
— Officer Riley (Uncredited)
Howard M. Mitchell
— Butler (Uncredited)
Ruth Rogers
— Woman at Charity Bazaar (Uncredited)
Sheila Ryan
— Hostess at Charity Bazaar (Uncredited)
Hugh Sothern
— Dr. Hatch (Uncredited)
Max Wagner
— Cab Driver (Uncredited)