Monk meets a visiting African widower who's determined to find the hit-and-run-driver who killed his wife near Monk's apartment. Monk begins to identify with the man and confuses his wife with Trudy.
Monk and Natalie are stranded in a small desert town and the detective spots a UFO. He soon discovers himself the center of attention, and is called in to investigate a dead woman discovered in the desert.
Monk and the police have a killer right where they want him... until the case goes to court and a hotshot lawyer demolishes the prosecution as he uses Monk's phobias against them
Natalie suspects a theater critic is responsible for a murder, despite the fact that he was present to review her daughter Julie's play at the same time the victim died.
Area residents receive unmarked dolls that seem to predict a series of strange deaths, leading many to suspect a voodoo curse is in play. The mystery hits close to home when Natalie becomes involved.
After Monk's insurance company refuses to pay for more private therapy sessions, he joins Dr. Bell's therapy group, where it appears that someone is murdering fellow patients.
When Sharona returns to San Francisco to handle legal issues related to an uncle's death, Monk suspects foul play and is torn between the differing styles of Sharona and Natalie.
Monk is called to a murder at the location where he first heard of his wife's murder, and while Monk figures out who the assassin is, he doesn't know that the one who ordered the hit is also responsible for the death of Trudy. Knowing that Monk will eventually put all the pieces together, he orders Monk's death, and when all hope seems lost, Monk discovers something which could finally end his 12-year nightmare.
After listening to Trudy's last message, Monk finally discovers who killed his wife. Racing against time before he dies of poison, he must make a fateful decision.