Colin Singleton
Colin is the main character of the story. He is a former child prodigy who wishes to prove that he is a genius by producing his own irrefutable formula like Einstein. Colin Singleton has dated nineteen girls by the name of Katherine, and every relationship ended poorly. His main flaw is his need to be praised and recognized.
Hassan Harbish
Hassan Harbish is the Muslim best friend of Colin Singleton. He is rather intelligent, but chooses to shrug off his responsibilities in feigned respect for his religion. Hassan is really Colin's only friend, and he initiates the road trip that changes Colin's life forever.
Lindsey Lee Wells
Colin and Hassan meet Lindsey Lee Wells when they travel to Gutshot on their road trip. She loves Gutshot and intends to never leave. She is in a relationship with a boy named Colin, who Hassan likes to refer to as TOC, or The Other Colin. Lindsey eventually separates from TOC, and becomes the first girl Colin has ever dated that does not bear the name Katherine.
Hollis
Hollis is a long time resident of Gutshot and mother of Lindsey Lee Wells. Hollis hires Hassan and Colin to work for her and interview old factory workers. Later on it is revealed the factory hasn't been making money in years and she's been disposing of stock so nobody would have to be fired from the factory. She is a mother of Lindsey and an extreme workaholic.
