Shahidah El-Amin is many things: scholar, cartographer, astronomer, mathematician, scientist, explorer, adventurer, and—when need be—two-fisted fighter. Setting out from Baghdad's legendary House of Wisdom during the Islamic Golden Age, Shahidah's quest brings her to 13th-century Britain…where the Welsh are whispered to possess the secret of eternal life. But Shahidah is not the only one after it…