As a novelist, A.M. Homes has developed a reputation for tackling sick themes — pedophilia, arson and spousal homicide are just the beginning. So it’s saying something that this memoir is in keeping with her best fiction. If you haven’t guessed by now, Homes is, indeed, the mistress’s daughter — the mistress being a 22-year-old who gave birth to her after a seven-year affair with her boss. Homes was subsequently given up for adoption, never meeting her birth-parents, and in this autumnal, frequently foreboding tale she unpacks the story of a search for her roots that may be called both a success and a failure. The book’s best achievement is the stretch of prose where Homes narrates the long-delayed day on which she finally met her biological parents at 31 years of age, a piece originally published in The New Yorker that must rank among her best writing ever. That essay forms the core of The Mistress’s Daughter, centering a book that goes beyond the confines of the typical memoir to confront the deep crises of identity and isolation redolent of the best existential novels. With a pared-down style recalling Hemingway and a postmodern mystery reminiscent of Paul Auster, Homes has written a very literary, very personal account of her own life, one with resonances far beyond her own experiences.