A former San Francisco police detective suffering from an extreme case of obsessive-compulsive disorder is called in to investigate an apparent assassination attempt of a mayoral candidate in which one of his bodyguards is killed.

When billionaire software magnate Sidney Teal is shot dead by ex-cop Archie Modine after allegedly turning mugger and another policeman mysteriously flees the scene, Stottlemeyer calls in Monk to investigate. Not only is the idea of a billionaire turning mugger hard to swallow, the circumstances of the mugging are suspicious. Why, for example, would a mugger wear knee and elbow pads? Meanwhile, Sharona threatens to quit (this time for sure) when her paycheck bounces, and Stottlemeyer is hounded by reporters demanding information on "Fraidy Cop." Unable to continue the investigation without Sharona's help, Monk returns to the seemingly unsolvable mystery of his wife's murder only to find that his "new" clue isn't new; he's already talked to writer Kelly Street three times. Sharona finds that selling lamps isn't nearly as much fun as working for Monk (with or without money) and comes to the rescue with a new clue involving Teal and Modine.