Annie Wilkes, [Stephen] King told me recently, was inspired in part by Mark David Chapman, who assassinated John Lennon hours after getting his autograph. As an author, King is familiar with fan enthusiasm gone awry. “There was a lot of backlash about the way that the ‘Dark Tower’ books ended,” he told me, referring to his multipart fantasy series. “Those fans were absolutely rabid about those books.” Not long after “Misery” came out, King and his son were at a baseball game when a man broke into his house with what he said was a bomb, claiming that Annie Wilkes had secretly been based on his aunt. “My wife ran out in her bare feet and called the cops,” King recalled, “and the guy was cowering in the turret of the third floor of our Victorian home.” The bomb turned out to be a bunch of pencils in a rubber band. Still, it unnerved King: his novel about a stalker fan had summoned a stalker fan. “People have gotten invested in culture and make-believe in a way that I think is a little bit unhealthy,” King said. “I mean, it’s supposed to be fun, right?”