The film follows Lori Reimuller, Meryl Streep, a devoted mother of three in a comfortable Midwestern family led by her husband Dave Reimuller, Fred Ward, a hard-working truck driver. The family seems stable, even planning a holiday to Hawaii, until Robbie Reimuller, Seth Adkins, their youngest son, endures two sudden, unexplained falls—one at school and another while playing with his brother. These episodes are followed by a medical investigation that begins with tests like a CT scan, a lumbar puncture, an electroencephalogram, and blood work. No immediate cause turns up, and Robbie is diagnosed with epilepsy after the seizures are labeled as epileptic in origin.
Robbie is started on phenobarbital, an old anticonvulsant known for cognitive and behavioral side effects. The drug’s harsh impact becomes hard to ignore as he experiences changes in mood and behavior, sometimes running berserk through the house and injuring himself. Lori urgently requests a medication change, and the regimen is altered to phenytoin [Allison Janney], with the dose of phenobarbital being tapered slowly, a process that brings its own frustration. Later, carbamazepine is added to help control the seizures.
The family’s mounting stress is compounded by medical and financial strain: their health insurance is deemed invalid, and Robbie’s care shifts from private to county hospital. In a bid to cover mounting bills, Dave takes on riskier truckloads and longer hours, and the looming prospect of foreclosure adds to the tension at home. As Robbie’s condition fluctuates, his seizures intensify, and he develops Stevens–Johnson syndrome, a serious skin reaction to the medication. He is admitted to hospital with a padded cot to prevent him from escaping, and the fear grows that he might become a “vegetable.” In a crisis, Robbie experiences status epilepticus, a life-threatening continuous seizure, prompting escalating doses of diazepam that fail to curb the episode, and eventually rectal paraldehyde is administered, a moment rendered starkly on screen.
The neurologist in charge, Dr. Melanie Abbasac, Allison Janney by reference in the cast, presents a stark, candid outlook and proposes surgery as a possible option. The plan would involve removing the top of the skull and placing surface electrodes on the brain to pinpoint the seizure focus more precisely than scalp EEGs allow. For Lori and Dave, surgery feels like a drastic last resort, and they seek alternatives while weighing the risks of such an invasive procedure.
Lori dives into epilepsy research at the library, searching for hope beyond medication. After long hours of study, she encounters the ketogenic diet as a potential lifeline, though a physician dismisses it as largely anecdotal. Persisting against initial resistance, she pushes to explore the diet, but faces formidable hurdles: they must arrange transport for Robbie to Johns Hopkins Hospital in Baltimore and secure ongoing medical support—something their finances cannot easily sustain.
In a pivotal moment, Lori makes a daring choice: she attempts to take Robbie out of the hospital to pursue a treatment appointment she has arranged, risking her custody of him in the process. A sympathetic nurse cautions that such actions could jeopardize their parental rights. Dave reconnects with an old family friend who is a licensed doctor, and the trio—Lori, Robbie, and the doctor—are accompanied by the nurse on a flight to Baltimore. The journey is tense, as Robbie endures a prolonged convulsive seizure aboard the plane, heightening concerns among the crew.
Upon arrival at Johns Hopkins, it becomes clear that Lori’s earlier appointment was not rescheduled and there are no immediate openings in the ketogenic program. After much pleading, Dr. Freeman agrees to accept Robbie as an outpatient. The pair stay at a convent in Baltimore as they navigate the system and await a path forward.
The diet’s explanation is provided by Millicent Kelly, Millicent Kelly, a dietitian who has guided ketogenic therapies since the 1940s. Robbie’s seizures begin to respond during the initial fast that kick-starts the program, and, despite the high-fat regimen, he adapts to the meals with surprising resilience. Remarkably, the seizures subside, his cognitive abilities return, and he appears to regain a sense of normalcy. The narrative emphasizes that Robbie’s improvements were closely tied to the diet, rather than medication alone. The film closes with a triumphant image of Robbie riding the family’s horse in a town parade, conveying a restored sense of hope for the future. The closing credits note that Robbie continued the ketogenic diet for a couple of years and has remained seizure- and drug-free since.
