Depending on one's point of view, Ferdinand Mount is either a political figure who writes novels or a novelist who has also put his wisdom to use in politics and political writing. One might also think of him as a gifted editor who finds time for writing fiction and political commentary. Since 1991 he has been the editor of TLS: The Times Literary Supplement, the most important British book review, and during the same decade he accelerated his production of fiction, publishing four novels between 1991 and 1998. The apparently unplanned series of novels and nonfiction books appearing under his name since 1967 has begun to take a more visible shape; four of his nine novels-The Man Who Rode Ampersand (1975), The Selkirk Strip (1987), Of Love and Asthma (1991), and The Liquidator (1995)-have been identified as a tetralogy called "A Chronicle of Modern Twilight," and two others-Umbrella (1994) and Jem (and Sam) (1998)-are...