Dr. Jack

Country doctor Jack Jackson is called in to treat the Sick-Little-Well-Girl, who has been making Dr. Saulsbourg and his sanitarium very rich after years of unsuccessful treatment.

• 
  Sam Taylor
• 
  Fred C. Newmeyer
• 
  Robert A. Golden

• 
  Harold Lloyd
  Dr. 'Jack' Jackson
• 
  Mildred Davis
  The Sick-Little-Well-Girl
• 
  John T. Prince
  Charles F. Haskell - Her Father
• 
  Eric Mayne
  Dr. Ludwig von Saulsbourg
• 
  C. Norman Hammond
  Jamison - the Lawyer
• 
  Jackie Condon
  Boy's Pal (uncredited)
• 
  Mickey Daniels
  Boy Patient (uncredited)
• 
  Richard Daniels
  Man (uncredited)
• 
  William Gillespie
  Card Player (uncredited)
• 
  Wally Howe
  Asylum Guard (uncredited)
• 
  James T. Kelley
  Card-Playing Father (uncredited)
• 
  'Auntie' Mackay
  Undetermined Secondary Role (uncredited)
• 
  Florence Mayon
  Card Player's Daughter (uncredited)
• 
  Oscar Morgan
  Undetermined Secondary Role (uncredited)
• 
  Charles Stevenson
  Asylum Guard (uncredited)
• 
  Anna Townsend
  Jamison's Mother (uncredited)
• 
  Dorothy Vernon
  Restaurant Hostess (uncredited)
• 
  Joy Winthrop
  Undetermined Secondary Role (uncredited)