President John F. Kennedy is dead.

Life can turn on a dime-or stumble into the extraordinary, as it does for Jake Epping, a high school English teacher in a Maine town. While grading essays by his GED students, Jake reads a gruesome, enthralling piece penned by janitor Harry Dunning: fifty years ago, Harry somehow survived his father's sledgehammer slaughter of his entire family. Jake is blown away . . . but an even more bizarre secret comes to light when Jake's friend Al, owner of the local diner, enlists Jake to take over the mission that has become his obsession-to prevent the Kennedy assassination. How? By stepping through a portal in the diner's storeroom, and into the era of Ike and Elvis, of big American cars, sock hops, and cigarette smoke. . . . Finding himself in warmhearted Jodie, Texas, Jake begins a new life. But all turns in the road lead to a troubled loner named Lee Harvey Oswald. The course of history is about to be rewritten . . . and become heart-stoppingly suspenseful.