A good Samaritan witnesses a cult style murder but the evidence doesn't add up. Mr. Monk goes undercover with the "Siblings of the Sun" to solve the crime.
When Monk's bank is robbed, he's desperate to help with the investigation; when Captain Stottlemeyer won't let him, Monk takes up an unusual position at the bank.
Natalie is frantic, to the detriment of Stottlemeyer's new car, when it appears a mad man is targeting his victims based solely on their name - Julie Teeger.
Heartbroken by the sudden death of Dr. Kroger, Monk rushes into homeownership and gets a little more than he bargained for when he hires a very persistent contractor.
Brilliant chess grandmaster Patrick Kloster's wife Linda Kloster goes to Monk saying that her husband is planning to murder her, and she wants him caught posthumously.
A boxer narrowly avoids a bomb, and Stottlemeyer believes it won't be the only attempt with a championship bout coming up. Meantime, Monk splits his time between the case and contemplating retirement when he finds he must pass a fitness exam.
Monk is smitten with an attractive former dancer and when she's accused of murder, he agrees to help her, even though all the evidence points to her, and continues searching--even after she confesses to the crime.
Monk's hundredth case, involving a serial killer, is covered by a TV news magazine, but while watching it he realizes that a second unknown killer was responsible for one of the murders.
Monk's hypnotic regression to his childhood begins to affect the case on which he's consulting - an actress who's disappeared, and the holes in her story when she's found after a deadly escape.
Monk's Christmas spirit, or lack thereof, is challenged when he takes a case from three homeless men who believe their friend was murdered, and Leland's epiphany sends him on a mission.