The Unknown Quantity
- वर्ष: 1919
- देश: United States of America
- शैली: Drama
- स्टुडिओ: Vitagraph Company of America
- कीवर्ड: lost film
- संचालक: Thomas R. Mills
- कास्ट: Corinne Griffith, Huntley Gordon, Harry Davenport, Jack McLean, Jack Ridgeway, F.R. Buckley
