The Lion of Petra is one of a series featuring Major James Schuyler Grim. The Lion is Ali Higg, a Bedouin nomad who has set up shop in the inaccessible valley of Petra, from which he raids Palestine. Having bested Higg and forced him to post bond of fifty thousand pounds as a promise of good behavior, "Jimgrim" must now help Higg if he wants him to hold to the agreement. He must take his force of twenty men and somehow subdue Higg's rival, Hassan Saoud, who calls himself the Avenger and commands an army of eight hundred.