A lusty tune played in an historical key centers about Olivier d'Angle, son of an English earl who has grown up in serfdom to the raiding Gazonneaux. Apprised of his heritage, grown to manhood, Olivier is about to strike out for Constantinople and his father when a dangerous falling out with Sir Lethold over a brutal rape-murder leads to the dungeons. Aided by ""Sir Bogardus"", who achieves a family vengeance against the Baron of Gazonneaux. Olivier escapes, shielded by Lethold's intended bride, Elaine, who shares a deep love with Olivier and nurses his wounds. At Constantinople, having left Elaine with her family. Olivier discovers his father is the leader of the Moslem forces and falls into the lethal arms of a Persian harlot. Roused by friends, he enters the stronghold where his father reigns and where Elaine is imprisoned by the Moslems after the treachery of Lethold: he succeeds in saving her for himself, killing off Lethold, and sending his father to another site of conquest. A Crusade story of familiar mien with blows aimed low.