There is a ferocious restlessness in Steven Millhauser's stories, a mingling of desire and dread. Among the showpieces in his mesmerizing new collection, Dangerous Laughter (Knopf): "Cat 'n' Mouse," which amazingly puts into words the familiar cartoon to bare the existential angst behind the familiar slapstick, and "A Change in Fashion," a tale of sartorial design gone mad that makes the emperor's new clothes look uninspired.