Stephen King is afraid of cellphones. Insects. Elevators. The number 13. Unhinged fans.

"I just write about what scares me," Mr. King said during an interview at his home in Bangor, Maine. "When I was a kid, my mother used to say, 'Think of the worst thing that you can, and if you say it out loud then it won't come true.' And that's probably been the basis of my career."

For...