In the past, Adrian Monk (Tony Shalhoub) was a San Francisco Police Department investigator, but the death of his wife, Trudy, led him to develop depression, exacerbate his obsessive–compulsive disorder and suffer from multiple phobias. Now, as a private detective, Monk investigates the murder of Nicole Vasquez (Michelle Addison). Later, a shooting occurs during a campaign rally, resulting in the bodyguard of mayoral candidate Warren St. Claire (Michael Hogan) getting killed. The incumbent mayor orders Captain Stottlemeyer (Ted Levine) to bring Monk in on the case, and, as Monk's former supervisor, reluctantly, he does.