When English teacher Beth Landow falls from the clock tower at Trudy's former high school, Monk is called in and quickly disproves the police theory of suicide. The trail of clues leads to a science teacher but he has an iron-clad alibi. Monk becomes a substitute teacher in the hopes of solving the case.
A skydiving student on spring break appears to have drowned in midair - a case strange enough to convince Monk to travel to Mexico to investigate. While there, he must deal with a myriad of phobias, the theft of his luggage, the shortage of his favorite brand of bottled water, and apparent attempts on his life, all while trying to unravel one or more murders that are not what they seem.
When a powerful CEO and his wife are shot to death in a deserted parking lot, the police investigate the husband's enemies. But Monk thinks it's all about the wife and the affair she was having with a handsome young ballplayer.
When a ringmaster is murdered by an acrobat in a crowded restaurant, Monk suspects his ex wife is responsible. But with her foot broken and in a cast, how could she have done it?
The world's oldest man dies the day before his birthday, and everyone but Stottlemeyer's wife, Karen, thinks it's just the result of old age. Karen enlists Monk's help to figure out what really happened.
Monk attends a popular new play starring Sharona's sister Gail. But when Gail appears to stab and kill her costar during the live performance, Sharona calls Monk in to investigate.
A series of mail bombs target three wealthy siblings, but Monk thinks one of the brothers is actually responsible. The problem is, he's been in a coma for the last four months.
Monk suspects the owner of a notorious playboy magazine is responsible for the death of his CFO, who died alone in a locked room of an apparent accident. So, how did he do it?
Monk's agoraphobic brother Ambrose asks for his help, convinced his neighbor has been killed by her husband. But all the husband seems focused on is winning the pies at the local fair.
Law student Julie Parlow's grandmother is kidnapped and held for ransom. But they don't have any money, so why did the kidnappers release her? And why did they feed her pizza?
A sniper causes a car accident that nearly kills Stottlemeyer's wife, Karen. Now it's up to Monk to solve the case and keep Stottlemeyer from doing something he might regret.
When Randy's mother marries a guy much younger than her he gets worried. When they go to some kind of couples retreat, he asks Monk and Sharona to go and keep an eye on her. So to go in they pretend to be married.
When an inmate is poisoned to death hours before he's due to be executed, Monk is brought in to solve the case and finds himself as the prison's newest resident.