Kellin Taylor, a 16-year-old with epilepsy, has not had a seizure in five months and is visiting the nation's most praised doctor. Because of his two-weekly visits to Dr. Tobin, he has been neglecting schoolwork, leaving his parents, Thad Taylor and Meg Taylor, disappointed that Kellin’s progress toward a normal high school life has slipped away from them.
To help his grades, he is assigned a tutor, Susie Fratelli, whom he immediately falls in love with. Susie Fratelli becomes a steady presence in his life, and, despite his shy nature, she takes an interest in him as well, inviting him to jog with her the next morning. All these changes coincide with a setback: Kellin experiences another epileptic seizure at night. The following day, Susie is initially upset that he didn’t show up for their jog, until Kellin shares the truth about his epilepsy. She isn’t scared off, and their bond grows even stronger.
Dr. Tobin grows worried about Kellin’s seizures, realizing that the drugs may no longer control them. He informs Kellin’s father, Thad Taylor, that an experimental brain surgery could be the only viable option, but Thad fears its risks and resists it. Kellin learns of the possibility through a letter and frets that his parents kept this from him. Unlike his parents, Kellin leans toward the operation and pursues it, even as his parents’ approval remains unresolved. He even contemplates suing for independence so he can decide for himself about the operation.
When Thad and Meg discover they are being sued, they seek expert advice. The professionals explain that while the operation could stop the seizures, other seizures might still occur. Meanwhile, Kellin is advised by his attorney Virginia Hagan to move out of the family home during the trial. The ensuing legal battle and media attention strain the family, leading Kellin to move in with Virginia, even as he feels guilty about the impact on his younger brother Harvey. The case forces Thad to transfer jobs, and Harvey feels neglected by his parents. Kellin’s doubts about surgery intensify as he endures his first seizure in Susie’s presence.
At the trial, Virginia calls Eli Rhodes, a former epileptic patient who underwent the surgery successfully. Kellin finds renewed motivation from Rhodes’s story and resolves to continue with the operation. As the trial nears its end, Kellin and Susie grow closer and share a kiss, adding a personal dimension to the proceedings. Judge Rosenstiel ultimately grants consent for the operation. Although Thad and Meg feel a sense of disappointment about the process, they set aside their quarrel with Kellin and pledge to support him through the upcoming surgery. The operation itself is challenging and lasts five hours, but it ends successfully. Kellin awakens surrounded by his family and his girlfriend, marking a new chapter in his life.
