• 
  Leonard Nimoy

  Cowell
• 
  Lew Ayres

  Dr. Thomas Clay
• 
  Julie Adams

  Joanne Clay
• 
  Monroe Arnold

  Dr. Duveen
• 
  Don Dillaway

  2nd VIP
• 
  Sue England

  Helen
• 
  Michael Fox

  Howard Link
• 
  Morgan Jones

  Chester

• 
  Walter Woolf King

  1st VIP
• 
  Ted Knight (I)

  Dr. Lessing
• 
  Thalmus Rasulala

  Technician (as Jack Crowder)
• 
  Robert F. Simon

  Gen. 'Red' Brockman
• 
  Garry Walberg

  Dr. Martin Sorbin
• 
  Robert Webber

  Robert Burke
• 
  Jason Wingreen

  Savadow