When a friend's mutilated body is discovered at a roadside park along the Kansas Interstate, Mike Bishop sets out on a quest to unravel the mystery of the man's death. But after his most promising lead disappears into the wintery depths of an Oklahoma lake, Bishop finds himself at a dead-end.

As he considers his few remaining leads, attorney Megan Armstrong asks Bishop to accept a missing person case. Megan fears the missing man, once a part-time investigator for her law firm, may have become involved with the wife of a client, a client who has since been murdered.

Bishop locates the missing man with little difficulty. However, upon questioning, the man reveals an unexpected detail that may connect the murder of Megan's client with that of Bishop's friend. Armed with the new information, Bishop enlists the help of former Marine Corps Sergeant, Abraham Lincoln Decker and together, they encounter an eccentric cast of barmaids, blackjack dealers, and geriatric bikers as they search to unravel the mystery that links the two murders.

The investigation eventually leads Bishop and Decker to Sidewinder, a small town in western Kansas where they uncover a slimy underworld of child prostitution, black market military weapons, and domestic terrorism. But before they can expose the secret militia organization responsible for the two murders, they must face a killer more monstrous than any they have ever imagined.