The Curse of the Pharaohs by Elizabeth Peters
Bored with the constraints of Victorian domesticity, Radcliffe Emerson and his wife, the doughty Amelia Peabody, take over an excavation in Luxor, after the eminent archaeologist Sir Henry Baskerville dies in mysterious circumstances. The English press is proclaiming, 'The curse of the Pharaohs has struck!' In Luxor they find the camp in disarray and Lady Baskerville surrounded by a most eccentric group of guests. Armed only with her trusty parasol, Amelia sets about bringing order from chaos, and the true cause of Sir Henry's death...