• 
  Lewis Collins

  regizor

• 
  Cyril Delevanti

  Professor Jackson Parker [Chs. 5, 6, 9]
• 
  Dennis Moore

  Agent Grant Farrell
• 
  Anthony Warde

  Martin Brandon [Ch. 10]
• 
  Joseph Crehan

  Police Chief Dan Blair
• 
  Virginia Brissac

  Cornelia Waldron
• 
  Byron Foulger

  Wetherby/Mr. M
• 
  Harry Strang

  William Brewster, scientist [Ch. 3]

• 
  Paul Sawtell

  music department
• 
  William Lava

  music department
• 
  Hans J. Salter

  music department
• 
  Frank Skinner

  music department
• 
  Dimitri Tiomkin

  music department