Medical examiner Laura Henning has two charred corpses and no answers. Both bear a mysterious tattoo but exhibit no known cause of death. Their only connection is a string of puzzling miracle cures. Her preliminary investigation points to a cult that possesses the fabled panacea--the substance that can cure all ills--but everyone knows that's impossible. Or is it? Laura finds herself enmeshed in an ancient conflict between the secretive keepers of the panacea and the equally secretive and far more deadly group known only as 536, a brotherhood that fervently believes God intended for humanity to suffer, not be cured. A reclusive, terminally ill billionaire hires Laura to research the possibility that the panacea exists. The billionaire's own bodyguard, Rick Hayden, a mercenary who isn't who he pretends to be, has to keep her alive as they race from continent to continent to find the legendary panacea before the agents of 536 can destroy it.