Yellow-Dog Contract - Ross Thomas

An ex-political operative is a master of dirty tricks, but now he's mixed up in something far worse: "Ross Thomas is without peer in American suspense" (Los Angeles Times).
There are few jobs that Harvey Longmire hasn't had. He's been a crime reporter, Louisiana state legislator, foreign correspondent, and—briefly—a decoy for the CIA. But he made his name as campaign trail fixer, an expert in the art of exploiting an enemy's secrets. For nearly a decade, Harvey was the sharpest man in the Beltway, but he quit in 1972, trading political dirty work for a quiet life on a farm. Now two old friends want him back in the game. A millionaire named Vullo has started a foundation to investigate conspiracies, and Harvey happens to be the expert on the most prominent case: the infamous disappearance of a man named Arch Mix. The trail is not as cold as Harvey thought. Soon he'll either find Mix—or suffer a disappearance of his own.