Colin grew up as a child prodigy and has always worked very hard at being smart. By the time he graduates from high school, he speaks almost a dozen languages and has appeared on a TV quiz show. He naturally creates a lot of anagrams with words, rearranging the letters into new phrases. His best friend Hassan is lazy, but also quick-witted and fun to be around, with much better social skills than Colin. Colin is depressed after his girlfriend, Katherine, breaks up with him on the day of their high school graduation. He also worries about not living up to the potential suggested by his childhood successes.
Hassan talks Colin into going on a road trip. The trip takes the two boys from Chicago to a small Tennessee town that claims to be the burial location of Archduke Franz Ferdinand, whose assassination precipitated World War I. The first person Colin and Hassan meet in the town is a girl named Lindsey. Lindsey knows how to be cool and make friends. Her boyfriend is also named Colin. Colin and Hassan call him The Other Colin—TOC, for short. Lindsey’s mother, Hollis, owns and runs the only factory in town, which makes tampon strings.

Hollis hires Colin and Hassan for a special project. She wants them to record interviews with the factory’s active and retired workers so she can put together an oral history of the town. While Colin and Hassan, with Lindsey’s help, go about collecting the interviews, Colin is also working on a project of his own. The Katherine that broke up with him is the nineteenth of a whole series of girlfriends named Katherine, all of whom dumped Colin. Colin tries to work out a mathematical formula that, given a little information about a romantic couple, predicts how long the relationship will last, and which partner will end it. Colin keeps refining the formula, using his nineteen Katherine relationships as data to test the formula’s accuracy. The last Katherine, from his senior year, was also his first girlfriend, back in third grade. He misses her terribly and at one point tries unsuccessfully to revive the relationship over the phone.

Meanwhile, Hassan has been making friends and has even gotten involved with Katrina, a friend of Lindsey’s. When Colin is invited to join everyone else on a feral pig hunt, he reluctantly agrees to go. Lindsey, who is starting to grow fond of Colin, takes him into the woods so he can get used to firing a shotgun. She then takes him to a cave hideout she has never shared with anyone else. The next day, a pig is tracked but no pig is shot. Instead, the hunt ends when Colin and Hassan get lost and come out of the woods to find Katrina having sex with TOC, Lindsey’s boyfriend. The rest of the hunting party, including Lindsey, arrives soon after. When Lindsey learns that TOC was cheating on her, a brawl breaks out.

The land where Lindsey and Colin practiced shooting, and where she has her hideout, belongs to Hollis. During an earlier interview with some factory retirees, Lindsey happened to learn, to her dismay, that Hollis is planning to sell the land. She and Colin also overheard Hollis talking on the phone about how to get rid of some unnamed materials without paying for garbage pickup. Hollis directed the person at the other end to bury the materials in a field near the factory’s warehouse. Now determined to find out what is going on, Lindsey takes Colin and Hassan on a trip to the warehouse, which is in Memphis. There they meet Hollis and learn that the unnamed materials are boxes and boxes of unsold tampon strings. Hollis no longer has enough buyers for the factory’s product, but she has not wanted to cut production, because that would mean laying off workers. Lindsey, Colin, and Hassan each come away having learned something from Hollis’s example of hidden service to her community and her employees.

In the end, Colin realizes that his memory is not as perfect as he thought, because he misremembered what happened to his relationship with Katherine number three. His formula is also a failure, because he and Lindsey are a couple even after the formula predicts they will break up. Colin’s formula is a kind of story, better suited for describing the past than for predicting the future. With his formula a failure, Colin puts his youth as a prodigy behind him. He is not unique. His future is as wide-open as everyone else’s.