Thomas Mollison, portrayed by Rhys Wakefield, relocates with his family to a new residence in the early 1990s. The story opens with his autistic brother, Charlie, creating a ruckus by banging a wooden spoon on the grass, as curious neighbors watch on. We soon discover their mother Maggie, played by Toni Collette, who is seen locking star-shaped stickers away in the bathroom cabinet. As Thomas prepares to navigate his new school and make friends, he grapples with feelings of anxiety and isolation, particularly noticing that his mother seems more attached to Charlie, played by Luke Ford. Despite Thomas's devotion to his brother, it’s evident that he longs for his mother’s affection.
As Maggie’s pregnancy progresses, her doctor advises her to rest due to complications related to pre-eclampsia. This shift inadvertently thrusts Thomas into the role of Charlie's caregiver, a responsibility he finds exceedingly challenging. One particularly chaotic episode occurs when Charlie, filled with energy, runs off, prompting Thomas to chase after him. Matters take a turn for the awkward when they accidently invade the privacy of a girl named Jackie while looking for a bathroom. Their encounter leaves Thomas red-faced, especially when Jackie later shows interest in him by attending a CPR class at school and visiting to return a forgotten hat.
Things spiral into chaos when Thomas, overwhelmed by the pressures of caring for Charlie—who uses sign language to communicate—locks him in a room out of frustration. This incident leads to a confrontation with Maggie, who reminds Thomas that Charlie may never lead a normal life. The family dynamic becomes increasingly strained, culminating in Simon, the father, insisting that Maggie spend her remaining pregnancy in the hospital.
As Thomas continues to navigate demanding days, he accommodates Charlie’s needs, including taking the special bus to school and dealing with the fallout from his brother’s outbursts. In a moment of passion and burgeoning teenage love, Thomas shares his first kiss with Jackie during a rainy adventure, which further complicates the relationship dynamics as the two grow closer. With Charlie often finding himself at the center of both joy and chaos, moments at home become a balancing act.
The family's life unravels into a mix of ups and downs, including celebrated moments like a birthday dinner that descends into embarrassment when Charlie's behavior becomes too erratic for guests. This friction pushes Thomas and Charlie further apart, leading to a climactic fight. However, amidst the turmoil, there are glimmers of hope and reconciliation, such as when Thomas impulsively dons a monkey costume with Charlie during a school play, showcasing their brotherly bond on stage.
Ultimately, the film concludes with a poignant moment between the brothers, leaving viewers to reflect on the meaning of acceptance and love amidst challenges, as Thomas humorously quips, “You just pissed on my leg, didn't you?” The laughter they share encapsulates a relationship strengthened by adversity and understanding.
