It begins in 1979, when twenty-one-year-old Petrel descends into the state-run purgatory of an overcrowded, understaffed Massachusetts mental hospital. Surrounded by inmates roaming the halls like drugged zombies and raving behind locked doors, well-meaning orderlies, jaded nurses, and patronizing doctors, Francis finds friendship with a motley assortment of fellow patients: a would-be Napoleon, a wise ex-firefighter, and a man obsessed with battling imagined devils. But there’s nothing imaginary about the young nurse found sexually assaulted and brutally murdered late one night after lights-out.