"Although it has strength and undoubtedly sustains the interest, "The Unknown," the latest screen contribution from Tod Browning and Lon Chaney, is anything but a pleasant story. It is gruesome and at times shocking, and the principal character deteriorates from a more or less sympathetic individual to an arch-fiend. The narrative is a sort of mixture of Balzac and Guy de Maupassant with a faint suggestion of O. Henry plus Mr. Browning's colorful side-show background." - Mordaunt Hall, The New York Times