While the world is waiting breathlessly for archaelogists to break into a long-hidden vault beneath the Great Sphinx, student Macy Sharif discovers that a religious cult is already raiding the site, looking for a map to the lost Pyramid of Osiris. Threatened by the cult, she seeks help from the American archaeologist, Nina Wilde. Nina and her husband, ex-SAS bodyguard Eddy Chase, go on a treasure hunt from the streets of Manhattan to a yacht off Monaco to a buried desert site, while they are stalked by a killer determined to uncover a six thousand year old secret.