This is a good season for readers still curious about the Kennedy era. Thomas has written a terrific biography of Robert Kennedy, weaving his way through the dense thickets of rumor, gossip, and charges with hardly a scratch, superbly sorting out the evidence with the experience of many years working with Washington's darker stories. R.F.K. emerges with all his volatility, idealized yearnings, quickness, and insecurity intact. It is not always an attractive portrait, but it is a very human one. Markedly different from and inferior to his older brother as either a statesman or a politician, Bobby was still indispensable to him. The real subtext of this book, however, is its recreation of the ugly netherworld of American political life in those years, when the shady practices of an older Washington mixed poisonously with the heady power and charged politics of the high Cold War. J. Edgar Hoover was a top predator in that world; his malignant influence shadows almost every chapter of this book.