Achmet Bey, a Turkish chieftain, catches one of his many wives in adultery and murders her lover. Throwing aside the cuckolding wife, he abducts his harem an innocent girl. However, a brave American who loves her comes to her rescue.

Captain Pemberton, an American soldier of fortune in command of the Black Horse Troop, falls in love with Sari, the beautiful beggar girl of Constantinople. Daring to enter a mosque one day, Sari witnesses wealthy sheik Hamid Pasha stab a young American to death. In order to silence the girl, Hamid decides to make Sari a member of his harem. Upon discovering the plan, Pemberton bribes an emissary to substitute his name for that of the sheik and the ceremony is performed. Learning of the deception, Hamid kidnaps the couple, imprisoning them in his desert stronghold where Sari makes a daring escape and rides to inform the Black Horse Troop of their Captain's peril. The troopers arrive just as Pemberton and Hamid are engaged in hand to hand combat and Sari rushes to her husband's side as he delivers the fatal blow to the sheik.