The Ape Who Guards the Balance - Elizabeth Peters

Prospects for the 1907 archaeological season in Egypt are looking somewhat dull to Amelia. As a result of Emerson's less-than-diplomatic behaviour, they have been demoted to examining only the most boring tombs in the Valley of the Kings - mere leftovers, really.And then, in a seedy section of Cairo, the younger members of the Peabody Emerson clan purchase a mint condition papyrus of the famed Book of the Dead, the collection of magical spells and prayers designed to ward off the perils of the underworld and lead the deceased into everlasting life. But for as long as there have been graves, there have also been grave robbers - and so begins a new adventure into antiquity. The season rapidly switches from dull to deadly as Amelia strives to untangle a web woven of criminals and cults, stolen treasures and fallen women - all the while under the unblinking eye of a ruthless, remorseless killer.