The New York Museum of Natural History receives their pilfered gem collection back, ground down to dust. Diogenes, the psychotic killer who stole them, is throwing down the gauntlet to both the city and to his brother, FBI Agent Pendergast, who is currently incarcerated in a maximum security prison for a crime he didn't commit. To quell the PR nightmare of the gem fiasco, the museum decides to reopen the Tomb of Senef. But when the tomb is unsealed, the killings begin again.