After finally solving his wife's murder, Monk decides to help his brother Ambrose by giving him an especially spectacular birthday present — a long trip so he can see all the things he's missed hiding in his house. On the way, Ambrose and Natalie's fears and Monk's tendency of finding murders wherever he goes complicate the vacation.
This book contains examples of the following tropes:
- Big Brother Instinct: At the end, Monk shoots a murderous driver to keep him from hitting the motor home and pushing it and Ambrose over a cliff.
- Busman's Holiday: Played with. Monk keeps running across murders during the vacation, but Natalie refuses to let him stop to investigate them, insisting he leave them to the local police and focus on making sure Ambrose has a good time. They wind up getting caught in a mystery anyway.
- The Cavalry Arrives Late: Stottlemeyer arrives at the end, but by that time Monk has already dealt with the perps.
- The Family That Slays Together: The murders that Monk and Natalie have wound up running across all through the book are the work of three aunts and their nephew, who have been "collecting" victims across the country.
- Intrepid Reporter: Dub Clemens, a man Monk and Natalie meet early on, turns out to be a reporter chasing a serial killer (actually a family of them), despite everyone else dismissing the supposed serial killings as unrelated. Thanks to Monk, he gets vindicated for his belief and gets credit for figuring out the truth in the official record.
- Kidnapped by an Ally: Monk comes up with the plan of drugging Ambrose's birthday cake so that they'll be able to get him into the motor home and get on the road before he wakes up. Ambrose actually calls the police to complain he's been kidnapped, but after seeing the situation, the police just leave.
- Kidnapped While Sleeping: Monk and Natalie, planning to take Monk's agoraphobic brother Ambrose on a motor home trip for his birthday, drug his birthday cake so they can get him into the motor home and get on the road without trouble. Ambrose explicitly calls it kidnapping when he wakes up, and even calls the police, but when the officers see the "victim" won't even leave the motor home, they decide it can't be that bad. Ambrose does eventually enjoy the trip somewhat.
- Offscreen Breakup: Natalie and Steven Albright were starting a relationship during the finale, but Natalie ends it before the beginning of the book - mainly because she found out he had A Girl in Every Port and saw no reason to stop.
- Shout-Out: Natalie compares Monk to Dirty Harry after he shoots one of the murderers of the week.
- Thrill Seeker: The three aunts turn out to be the dark variety; they travel cross-country killing people for kicks.
- Why Did It Have to Be Snakes?:
- Ambrose is still terrified of being outside his own house. He eventually adjusts to the motor home, but spends very limited amounts of time outside it and once can't bring himself to leave it to save his life.
- Natalie's fear is more played for laughs; she gets very nervous around motor homes after her father took her and her friends to see Race With the Devil when she was young. She copes well, but the movie becomes a Running Gag throughout the book.