Intern forensic pathologist Dr. Riley McKay has noticed irregularities in autopsies at the Allegheny County Coroner's lab. Suspecting foul play, she seeks help from Dr. Nick Polchak, the "bug man" renowned for his ability to solve murders by analyzing the insects on victim's bodies. Nick and Riley uncover a sinister link between the lab's director and PharmaGen, a start-up drug company specializing in genetic research. They also discover that PharmaGen fronts an underground system to procure transplant organs for wealthy clients by finding and murdering matching donors. But PharmaGen learns of their security breach and orders the couple destroyed. While staying a step ahead of PharmaGen assassins, romantic attraction develops between Nick and Riley. But the attraction is complicated by a tragic secret that Riley hides — a secret closely tied to one member of PharmaGen's operation which propels the novel to its astonishing conclusion.