Toward the middle of the twelfth century King Roger II, the Norman occupier of southern Italy and Sicily, desired to have an accurate map of the world. The scholars most known in the field of geography were Moslems, some of whom were famed for the personal travels they undertook. One of these men, Mohammed al-Idrisi, was sought out by Roger for his extraordinary knowledge of the known world. Near the end of his life, Roger was presented with an atlas of pure silver weighing over 400 pounds. By all accounts it was a masterpiece of artistry and, for the age, scholarly sophistication. It was al-Idrisi's jewel. However, in the chaos that was Sicily's heritage, it was long thought the silver atlas had been melted down by one group or another, a heartbreakingly lost object of beauty and scholarship. Iowa PI Bertrand McAbee is approached by a woman of a certain age to investigate the savage beating of a Tunisian doctoral student from the University of Iowa. McAbee, a former classics professor, takes on the matter against his intuition. As in so many of his cases it is not long before it morphs into a hugely complicated puzzle. Those pieces are made of murder, duplicity, and theft - all to the purpose of forwarding the agenda of an aristocratic world of secrecy where hoarding of cultural artifacts is commonplace. McAbee will enlist the assistance of his agency's best people as he comes to realize that a trip to Sicily will be necessary. There, with the assistance of a Benedictine abbot, McAbee will begin to understand the extraordinary danger that haunts one of his most perplexing cases.