The epigraph is a quote from a song by the protagonist’s favorite band, Konniption, titled “Come As You Were.”

Ash is an American teenager who plays on his high school football team, the Tibbetsville Tsunamis. He is the first-person narrator of Game Changer and describes himself as a white, well-intended but occasionally misguided teenager. While playing the first game of the season, Ash experiences a strange cold feeling when he is hit during a play. He initially brushes it off, per his family’s motto of “walk it off,” even though it leaves him dizzy. While driving back home after a celebratory dinner with his team, he fails to notice a stop sign and is nearly struck by an oncoming vehicle—the reason he missed the sign, he soon realizes, is because all stop signs are now blue instead of red. When he comments on it, everyone tells him that has always been the case.

Ash continues to notice details in his life that are now different, such as football team colors and mascots. He confides in Katie, a female friend he has some romantic interest in, and Leo, his best friend and teammate.