When the body of a gunshot victim rolls into the Santa Fe morgue, it should be a day like any other for medical investigator Lillian Cruz. Yet upon examination, the corpse appears to be over a hundred years old with smallpox scars, and an odd wound protrudes from the victim's leg. Lodged in the femur is a bullet shaped like a musket ball, which looks like it was fired during the Civil War and had remained in the victim's leg ever since. Rattled by the discovery, Cruz instructs her assistant to take specimens to the state authorities immediately. Minutes later, Cruz is kidnapped. The Defense Intelligence Agency calls in former war correspondent Ethan Warner and his partner, Nicola Lopez, to discreetly investigate the disappearance. And very quickly, a relatively simple case turns into something much more sinister. With each new lead they uncover, Warner and Lopez are inadvertently bringing a warped and dangerous individual closer to achieving a catastrophic goal: immortality.