Set in ancient Egypt, Pharaoh's wife Ayashet loves the immortal priest Inmutef, who loves the slave-girl Selena, who loves another. Ashayet kills Selena. Pharaoh banishes Ashayet, entombs and mummifies Inmutef. But Ashayet also is immortal, having bathed in the River of Life. Professor Niven discovers the whereabouts of Inmutef's tomb and sets out for Egypt with his daughter Nancy. Almost at once strange things happen. When the tomb is opened, the mummy behaves very peculiarly indeed. Plots and counterplots, ancient and modern, culminate in a series of shattering experiences for all concerned.