• 
  William Nigh

  regizor

• 
  Harvey Gates

  scenarist

• 
  Bela Lugosi

  Dr. Melcher
• 
  Joan Barclay

  Alice Saunders
• 
  George Pembroke

  Dr. William Saunders
• 
  Clayton Moore

  FBI Agent Richard 'Dick' Martin
• 
  Robert Frazer

  Amos Hanlin
• 
  Edward Peil Sr.

  Ryder

• 
  Robert Fiske

  Phillip Wallace
• 
  Irving Mitchell

  John Van Dyke
• 
  Kenneth Harlan

  FBI Chief Colton
• 
  Max Hoffman Jr.

  Kearney
• 
  Frank Melton

  agent FBI
• 
  Joseph Eggenton

  Stevens, the butler
• 
  I. Stanford Jolley

  The Dragon

• 
  Jack Cheatham

  Poliţist

• 
  Jack Dietz

  producător
• 
  Sam Katzman

  producător
• 
  Harvey Gates

  adaptare de
• 
  Arthur Reed

  imagine
• 
  Johnny Lange

  coloană sonoră