When high school teacher Caelum Quirk and his wife, Maureen, move to Littleton, Colorado, they both get jobs at Columbine High School. In April 1999, while Caelum is away, Maureen finds herself in the library at Columbine, cowering in a cabinet and expecting to be killed. Miraculously, she survives. But when Caelum and Maureen flee to an illusion of safety on the Quirk family's Connecticut farm, they discover that the effects of chaos are not easily put right.

While Maureen fights to regain her sanity, Caelum discovers five generations' worth of diaries, letters, and newspaper clippings in his family's house. As unimaginable secrets emerge, Caelum grapples with the past and struggles to fashion a future from the ashes of tragedy. His quest for meaning is at once mythic and contemporary, personal and quintessentially American.