Tom Heath, Nicholas Galitzine is a withdrawn teenager in South London who lives with his single mother, Mary Lisa Dillon. He dreams of becoming a rock musician, but school life is crowded with bullying—especially from his rival Damien James Tarpey—and he defensive hides his passion from Mary, who disapproves of music because her estranged husband’s failed career as a musician is still a painful memory. Tom carries the weight of loneliness, the sting of isolation, and the old wounds of self-harm, which he tries to manage by strumming the guitar he loves.
When a new tenant moves into their council flat, Tom meets Max Stone, a former American rock guitarist who vanished years earlier after his young son drowned and he fled tax fraud charges. Presumed dead by many, Max lives in hiding, blasting music day and night. Fascinated, Tom begs for lessons. Max initially refuses, but Tom’s boldness leads him to threaten to reveal Max’s survival, and gradually the two form an uneasy mentorship. As Tom learns, the two gradually grow closer, with Max slowly warming to the boy. Mary, unaware of the secret lessons, begins to feel a growing sense of companionship with Max, sharing meals and conversations. When she discovers that Max has been teaching Tom in secret, she feels betrayed and lashes out, accusing him of being unfit to guide a child. Shaken by her words and haunted by guilt over his own son’s death, Max leaves a letter for Tom and steps back from their lives. Tom sinks into depression and relapses into self-harm.
Soon Tom is approached by Felix, a girl from Damien’s band who is impressed after seeing a video of Tom playing with Max. She invites him to contribute as a songwriter, and Tom agrees, hoping the collaboration will validate his talent. But Damien steals his work and threatens to expose Max’s survival to the authorities, leaving Tom feeling cornered and desperate. On the rooftop, Tom contemplates suicide, but Max arrives to pull him back from the edge and urges him to channel his pain into music instead of self-destruction.
Determined to prove himself, Tom enters a local battle of the bands. Stage fright nearly paralyzes him at first, but Felix stands by his side, helping him push through. Midway through the performance, Max makes a surprising return—clean-shaven and revamped—joining Tom on stage. The duet electrifies the crowd, and videos of the performance spread across the internet, fueling a surge of support. The authorities arrive as Max is arrested for tax fraud, and Tom begs him to run, but Max chooses to face justice, accepting a three-year prison sentence. Tom continues to visit him with Mary by his side and begins a romantic relationship with Felix. The viral video of Tom and Max brings in crowdfunding that raises £500,000, giving Tom the recognition he had long sought.
Years later, Max is released from prison, and Tom has grown into a confident young musician. The two reunite, performing together once more as Tom’s dream of rock stardom comes full circle.
