In 1127 A.D., several English crusader knights bury an Egyptian ruby within the tomb of one of their members. In present-day London, a construction crew discovers the tomb and a mysterious man is authorized to investigate the site. Ominous reporting on the news notes that people are not as far from important relics of the past as they realize.
In a flashback to the New Kingdom era, Princess Ahmanet is first in line to succeed her father Menehptre until his second wife gives birth to a son. Determined to claim the throne for herself, Ahmanet summons Set, who agrees to help her if she uses a mystical dagger known as the Dagger of Set to transfer his spirit into a corporeal form. After killing her family, Ahmanet attempts to sacrifice her lover to Set but is captured by her father's priests and condemned to be mummified alive for eternity. Her sarcophagus is buried in Mesopotamia and submerged in a pool of mercury so that her monstrous form will not escape.
