After losing his job with the San Francisco Police Department for three years because of his obsessive/compulsive disorder, Monk now is a private investigator consultant. Captain Stottlemeyer, his former boss, reluctantly requests his aid to discover the would-be assassin of mayoral candidate Warren St. Claire.
The police finally got a lead on the would-be assassin, but he manages to escape, in part because of Monk's fear of heights. Sharona then convinces the deputy mayor to let Monk continue his investigation despite the objections from Captain Stottlemeyer.
A panicky woman driver goes off the road thanks to a skid block placed by her husband, former police commissioner Harry Ashcombe. Dolly Flint, a psychic who was arrested three times on bunko charges by Captain Stottlemeyer, wakes up in her car next to the site of the staged accident. She believes that she was led to the site by the dead woman's "aura," but Monk is doubtful. Instead, Monk suspects that Ashcombe is the real culprit behind his wife death.
A judge called 911before her death, and identifies the man who is about to murder her as rich and obscenely fat financier Dale Biederbeck. But Dale the Whale weighs over 800 pounds and could never have made it to the scene of the crime, despite the 911 call and the testimony of a ten-year-old witness. Biederbeck had sued Monk's wife for libel before and this gives Monk the added incentive to find him guilty.
Officer Adam Kirk, an old friend of Stottlemeyer's, steps off a ferris wheel to find the young man he was riding with, dead from a knife in his chest. He is then arrested for murder. Stottlemeyer enlists Monk's help to investigate the case unofficially, even though Monk believes the hair-triggered cop is guilty. Monk then discovers that the bruises on the victim's body were self-inflicted.
While he was about to prepare his dead wife's favorite dinner in her old house to celebrate the anniversary of the day they met, Monk realized he is in the wrong house and got arrested for unlawful entry and then taken to Medford Psychiatric Institute for forty-eight hours of psychiatric observation. His roommate, John Wurster informs him of an unsolved murder four years earlier, while another inmate, Manny, involves him in a quest to discover Santa Claus on the asylum roof. But with Dr. Lancaster's orders not to play detective during his stay at Medford, Monk finds his quest to solve the two cases to be quite hard.
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, Monk is call in to investigate. In meanwhile, Sharona threatens to quit when her paycheck bounces, and Stottlemeyer is hounded by reporters demanding information on "Fraidy Cop." Without Sharona's help, Monk couldn't continue with the investigation. Sharona herself, finds that selling lamps isn't nearly as much fun as working for Adrian and so, comes to the rescue with a new clue involving Teal and Modine.
Songs: George Thorogood & the Destroyers -- Bad to the Bone
When a lawyer and his assistant are murdered, a disgruntled client whose burnt file is found in the wastebasket became the main suspect. But when he is also found dead, Stottlemeyer began to suspect his neighbor, who has been feuding with him for two years. Monk, himself is attracted to Monica, the neighbor who bears a slight resemblance to Trudy.
A woman is murdered during the San Francisco marathon and Monk suspects her married lover, Trevor McDowell, even though he has a solid alibi which is he was running in the race during the murder. In the meantime, Monk has the chance to visit his hero, an aging runner from Nigeria whom Sharona briefly suspects may be the murderer's accomplice--a theory Monk refuses even to consider.
Monk's vacation with Sharona and Benjy turns into work when Benjy witnesses a murder. But no body can be found. Benjy can't convince anyone except Monk and the hotel's security chief that he's not lying. Then, Benjy spots the body but it disappears again. With his time at the hotel almost up and the body still has not been found, Monk try to solve the case before it is too late.
A wealthy businessman is apparently killed in an earthquake, but Monk suspects his wife to be the real killer. Monk's condition worsens because of the trauma of the earthquake. He began to talk gibberish and he need to recover soon to be able to communicate his suspicions to the beleaguered captain. Sharona and Benjy are forced to spend the next few days with Sharona's sister, Gail when they were not allowed back into their home because of the earthquakes. Monk, too moved in with them.
The famous country singer Willie Nelson becomes the prime suspect when his manager is murdered, but the only witness to the crime, is a blind woman. At first, Stottlemeyer is reluctant to arrest the famous singer on such shaky evidence, but a video tape shows that Willie is indeed guilty. But, Monk thinks otherwise. Because Trudy was a devoted fan of Willie, Monk sets out to prove the singer is innocent.
Monk has to choose between being on his own without Sharona and flying cross-country to New Jersey. He overcomes his fears and boards the plane with Sharona. After annoying every passengers and crews with his first-time-flyer questions, he becomes even more unsettled when he suspects one of the passengers has murdered his wife and the woman accompanying him is an impostor. He then called the captain and persuaded Lt. Disher to search the airport for a body. While Monk was trapped in the toilet, another murder is committed. Monk must solve the case before the murderous couple board their plane for Paris.