Who but Stephen King would turn a Port-O-San into a slimy birth canal, or a roadside honky-tonk into a place for endless love? A book salesman with a grievance might pick up a mute hitchhiker, not knowing the silent man in the passenger seat listens altogether too well. Or an exercise routine on a stationary bicycle, begun to reduce bad cholesterol, might take its rider on a captivating — and then terrifying — journey. Set on a remote key in Florida, “The Gingerbread Girl” is a riveting tale featuring a young woman as vulnerable — and resourceful — as Audrey Hepburn’s character in “Wait Until Dark.” In “Ayana,” a blind girl works a miracle with a kiss and the touch of her hand. For King, the line between the living and the dead is often blurry, and the seams that hold our reality intact might tear apart at any moment. In one of the longer stories here, “N.,” which recently broke new ground when it was adapted as a graphic digital entertainment, a psychiatric patient’s irrational thinking might create an apocalyptic threat in the Maine countryside…or keep the world from falling victim to it.