In 1969 Jock Yablonski bolted from the corrupt leadership of the United Mine Workers Union and formed a new wing to unseat Tony Boyle, then UMW president. This unexpected attack (Yablonski had been no angel as an underling) moved Boyle to put out a contract on his new enemy. After the union leader's crooked reelection (later invalidated by the federal government), three hit men sneaked into the Yablonski home and shot him, his wife and daughter. Within months one of the hit men talked. Enter Philadelphia's leading assistant district attorney Richard Aurel Sprague, who had won 64 first-degree murder convictions. He determined to get the top killer who'd issued the contract. Over a three-year period he convicted all the smaller fry in the case, one by one, working his way up the union ladder until at last he dropped a steel net on Boyle himself. The murders have their gruesome fascination, but Sprague's hounddoggery is what gives the book its best moments. Where Brown focuses principally on Sprague, Trevor Armbrister's recent Act of Vengeance (p. 1021) is more sensitive to motives and the mentality of the miners. Both books tell the same grisly story, but Brown's portrait of Sprague in pursuit is more relentless and arresting.