From New York Times bestselling author Mira Grant comes the final book in the terrifying Parasitology series. The outbreak has spread, tearing apart the foundations of society, as implanted tapeworms have turned their human hosts into a seemingly mindless mob. Sal and her family are trapped between bad and worse, and must find a way to compromise between the two sides of their nature before the battle becomes large enough to destroy humanity, and everything that humanity has built. . . including the chimera. The broken doors are closing. Can Sal make it home? "A riveting near-future medical thriller that reads like the genetically-engineered love child of Robin Cook and Michael Crichton." —John Joseph Adams on Parasite More from Mira Grant: Parasitology Parasite Symbiont Chimera Newsflesh Feed Deadline Blackout Feedback Rise