Duncan discovers a journal belonging to what he thinks is a serial killer and he uses his knowledge of profiling as well as the clues from the journal to try to decipher who the serial killer is and who are his intended victims before the serial killer strikes. Duncan is a bit of a teenage delinquent who has been sent to work at the Toronto Transit Commission's lost and found in order to fulfill his two-months of community service. He and his friend Wayne were sentenced to community service after Wayne convinced Duncan to break into a new apartment building to steal an expensive toilet that they could sell to his uncle for some quick cash. The two teens end up getting caught when the toilet falls down the stairs and alerts the cop on duty that night.
At his new job, Duncan finds a journal chronicling some person's sick experiments with mice but he doesn't know whether he should report it since the journal has no details about who its author is. Duncan continues reading the diary and finds out that the writer might have been responsible for a recent fire in his neighborhood. As he reads further, he notices that the person seems to be chronicling all his crimes since he was young until he's older. Duncan finally reads that the person is tired of the “little crimes” and wants to do something big and he hints in his journal that it may involve women. The author keeps tabs on the train schedules of certain women and even gives them nicknames. Duncan nicknames the author Roach, and decides to try to find out who he is and whether the journal is referring to real people.
In his journal, Roach keeps track of a woman nicknamed Cherry for her red hair, who boards the train at 10:40 AM, details which Duncan uses to track down this mysterious woman. Duncan is surprised that Cherry really does exist and he tries to follow her to see if anyone near her might fit the profile of Roach, however he ends up spooking her, instead. Duncan reads up on how FBI agents profile a serial killer and finds out that cruelty to animals and arson are at the top of the list. Duncan finally realizes he might be dealing with something more serious than he thought so he decides to report it to the cops. Unfortunately, the cops don't take him or the journal seriously so Duncan decides he's the only one who might be able to save the lives of the women that Roach is targeting. He decides to ask his friends Wayne and Vinny to help him out.
After researching incidents relating to animal mutilations and fires, Vinny narrows down that Roach might be living somewhere in a neighborhood called Wilson Heights – the place where Cherry also lives. According to the journal and further research on FBI profiling, Duncan is sure that Roach is white and lives with his Grandmother. One of the pages of the journal is scribbled on a receipt that has been glued to the journal. After carefully extracting the receipt, Duncan finds out that Roach likely works at a hardware store, as the receipt is dated a year ago and lists an employee discount. After visiting the store, they figure out that Roach is likely not a direct employee of the hardware store but rather a security guard. At the security guard office, they notice a thin, skinny youth who they nickname Red and put on their suspects list. They also put a huge, muscular man – nicknamed Jumbo – on the list.
The next day, Duncan follows Jumbo while his friend Vinny follows Red. Jumbo already doesn't fit Duncan's vision of Roach as he gets on in a middle train compartment while Roach apparently prefers the front train compartments. Also, later that night, Jumbo meets up with his girlfriend and Duncan thinks that serial killers usually don't have relationships. Vinny reports that Red isn't likely Roach either as he lives outside the Wilson Heights neighborhood and has a wife, kids and a dog. A few days later, Duncan hears on the news that a woman was pushed onto an on-coming train and the suspect is a Hispanic man. He wonders if this is Roach but Vinny is still sure that Roach is a white guy.
One day, a man wearing thick glasses comes to the transit Lost and Found in search of a leather bound journal. Duncan is sure this is Roach. He lies and pretends it never got turned in but disguises himself and follows Roach all the way home. After Roach leaves the house, Duncan enlists his friend Wayne to pick the lock on Roach's house. Inside, they see Roach's grandma, who is deaf. This makes Wayne nervous and he tells Duncan that he's going to leave. After Wayne leaves, Duncan sneaks into the basement. He finds lots of jars of formaldehyde with animals and animal parts in the basement as well as photographs of women. Just before Duncan leaves, he notices there is another door in the basement that has a slot in it, big enough to push a plate through. Inside the cell-like room, Duncan finds a bucket but nothing else. He thinks that the room hasn't been used, yet. He's about to leave when Roach returns. The only place he can hide is inside the cell. Roach notices that someone's been in his basement and he makes a move to open the door of the cell. Duncan throws all his momentum at the door and knocks Roach off balance. Roach chases Duncan all the way to the subway train where Duncan is cornered. Roach pushes Duncan onto the tracks as a train is coming but Duncan manages to roll off the track and under the platform of the train. Roach loses his balance and falls onto the tracks where he is hit and killed by the on-coming train.
The story ends with Duncan recuperating from his injuries and pretending that he can't remember why Roach was chasing him except that he thought he was being mugged.
Best part of story, including ending:
I thought it was interesting that Duncan came upon this interesting adventure while working at the Toronto Transit Authority's Lost and Found. I specifically liked the idea of using the clues left behind in a nondescript journal and being able to pinpoint the different "characters" described in the journal by finding them on the subway.
Best scene in story:
My favorite scene was when Duncan is hiding in the cell and Roach finds him. It was a very tense and thrilling moment. Good thing Duncan had the guts to use the element of surprise to get away otherwise who knows what Roach would have done to him.
Opinion about the main character:
I like that Duncan isn't exactly the smoothest amateur detective ever portrayed in a teenage mystery novel. Instead, Duncan is a bit bumbling and careless but this makes him more relatable and makes the story more humorous for the reader.