Deputy U.S. Marshal Matt Battles is being blackmailed—by President Chester A. Arthur. The commander in chief needs someone to discover why Hatfield J. Warful is gathering every notorious gunslinger in the West at his home in Slaughter Canyon. Thanks to a falsified news report planted by the Secret Service, Battles is now wanted for robbery and murder, leaving him no choice but to infiltrate Warful’s gang by posing as an outlaw on the run. But Warful’s trigger-happy gunfighters share some unpleasant history with the supposed ex-Marshal, and they don’t care which side of the law he’s on. And if Battles doesn’t have enough worries being targeted by both lawman and outlaw alike, failing his mission could result in a second Civil War....