"How did I go from being a rock star to being a fat fuck no one cares about?" That's what one of the characters asks in Jennifer Egan's A Visit from the Goon Squad, and through most of the book, the author stays busy answering that question. The winner of the National Book Critics Circle Award for fiction, this wild, unpredictable novel starts with Bennie Salazar, a former punk rock star turned music producer, and his assistant, the klepto Sasha, in sorta-present-day New York. Afterward, it switches back to Bennie's troubled glory days in the San Francisco area; then suddenly, we're having to read the book sideways; and then we're in the future with a settled down Sasha. The time-switches and format quirks are standard fare for Egan, whose reputation for lucid, insightful metafiction preceded the release of Goon Squad. She has become a master of what can often be, in lesser writers' hands, annoying pretensions; and in fact, Egan makes this novel the proof of her own exciting talent as well as the value of metafiction itself. Yes, there's a discernible plot and developed characters, not to mention plenty of humor and graceful writing, but Egan, more than anything, seems to be exploring questions of youthful rebellion and what happens to it with age, along with the corruption that too often accompanies success. In a time when it's easy to be discouraged about the state of American fiction, Egan is a bright and quirky light.