Tom Perrotta began writing his postapocalyptic novel The Leftovers (St. Martin's, Aug. 30) during the economic crash of 2008, when Americans began a journey through psychological trauma after losing their jobs and their homes.

The premise of Perrotta's new book is: What if the Rapture actually happened? "I became aware at the time that there are moments when people can't conceive of a future," Perrotta says. "We were experiencing an epidemic of grief that I'm not sure we've recovered from yet." He poured this concept of lingering grief into the narrative of The Leftovers, which focuses on four members of a family that survives a world-shattering event in which people randomly disappear, dividing the world into Before and After. "I believe that the basic human condition is to be bystanders of disaster," Perrotta comments, adding that what most people don't realize is that the biblical Rapture is followed by seven years of tribulation.

Perrotta has written about evangelical Christianity before, in The Abstinence Teacher, but in his new book he treats the Rapture "as more or less a secular event, rather than a fulfillment of a Christian biblical prophecy." In The Leftovers, the Garvey family, the book's main characters, aren't religious at all until the mass disappearances occur. The book charts the spiritual journeys that two members of the family begin after the traumatic event. There is humor in the novel that is typical of Perrotta's writing, but the author found himself taking a stylistic turn as he progressed with the book. "I wanted to write a funny postapocalyptic book, but the grief in the story added a different dimension," says Perrotta.

The Leftovers is something of a departure for Perrotta, who is also the author of the highly acclaimed novel Little Children. "I've been writing long enough now that I've become a different writer," he says. "The books are not so much about me. I'm trying to work on bigger canvases and broaden my audience in the process." His hope is that his longtime readers will come along for the experience of The Leftovers, but that the novel also might appeal to a different group. "The premise of the book might interest readers who gravitate toward the intersection of genre fiction and literary fiction—people who liked The Road or The Handmaid's Tale or Never Let Me Go."

Perrotta signs ARCs today at 2:30 p.m. in St. Martin's booth (3352).