Salim is a young merchant's son in the port of Acre, newly recaptured from the Franks by Saladin. His is an uneventful life, spent playing, sitting in the sun, and using his lameness as an excuse to avoid work. But uncomfortable rumours about another infidel crusade are beginning to surface, the imams are preaching jihad, and Salim's father apprentices him off to a Jewish doctor to keep him out of harm's way. Doctor Musa is a kindly man and a highly skilled physician, but he doesn't think a great deal of Salim's dreams of battle glory. On their way to Jerusalem, to avoid the coming siege, Doctor Musa is commandeered to serve Saladin himself and so Salim has a first-hand view of the siege and its battles. He is outside the walls of Acre while his family are suffering inside.