At the last count, J.D. Salinger’s seminal work The Catcher in the Rye, had sold 65 million copies. At the book’s early and extraordinary success, when the world’s press began to beat a path to his door, an increasingly reclusive Salinger responded by holing up in a bunker, and refusing to give any interviews. He died aged ninety-one, in early 2010, but in all that time no one penetrated his famous reserve, although three books have been ...