In 1961 Liverpool, Brian Epstein, portrayed by Jacob Fortune-Lloyd, is the accomplished manager of his family’s record store, NEMS. The store becomes a focal point in the local music scene as he receives a wave of requests from enthusiastic teenage girls wanting the German single “My Bonnie” by an emerging Liverpudlian band known as the Beatles. Intrigued by their growing popularity, Brian decides to visit the Cavern Club for a firsthand experience of their performance. The energy of the crowd, predominantly made up of young fans, astonishes him. Despite being a novice in the music industry, Brian confidently proposes to become their manager, believing his background in retail gives him an edge in understanding their audience. The Beatles welcome his offer, and with Brian’s guidance, they agree to enhance their public image by adopting a more polished appearance, donning matching suits and haircuts.

As 1962 rolls in, Brian secures an audition for the band at Decca Records, yet the meeting does not go as planned. Decca’s executive, Dick Rowe, played by Alex MacQueen, questions Brian’s motivation for leaving a comfortable life to manage a group like the Beatles. However, he remains persistent and takes the audition tape to various other record labels, but faces rejection at every turn. Fortunately, he gets an opportunity to meet George Martin, the head of Parlophone, and persuades him to let the band audition. Their performance receives positive feedback, although Martin advises Brian to replace drummer Pete Best. After bringing in Ringo Starr, the Beatles achieve great success with their initial singles, “Love Me Do” and “From Me To You,” launching them into the realm of national acclaim.

Throughout 1963, Brian expands his management roster, bringing several more Liverpudlian talents into the fold, including Gerry and the Pacemakers, Billy J. Kramer and the Dakotas, and Cilla Black, played by Darci Shaw, who initially worked as the Cavern’s coat check girl. However, an unexpected and troubling event arises when Brian learns that a man involved in a sexual encounter with him is attempting to blackmail him. While his parents, Harry Epstein (played by Eddie Marsan) and Queenie Epstein (played by Emily Watson), lean towards involving the police, Brian is adamant about settling the matter privately to protect his privacy. His mother’s concern for his safety leads to a heartfelt exchange, at which point he discloses his plan to move to London to better handle the Beatles’ burgeoning fame. As Brian’s managerial responsibilities escalate, so do his struggles with substance abuse as he turns to barbiturates and stimulants to cope.

By 1964, Brian takes a pivotal trip to America, where he aims to secure the Beatles a spot on The Ed Sullivan Show. During this journey, he crosses paths with an aspiring actor named Tex Ellington, played by Ed Speleers. Their brief affair blossoms into a complicated relationship, with Brian urging Tex to come visit him in London. The Beatles’ dazzling performances on Sullivan, coupled with their vibrant single “I Want to Hold Your Hand,” propel them to international fame, leading to a whirlwind American tour. Yet, despite his professional triumphs, Brian grapples with profound loneliness. He takes Cilla as his date to his brother Clive’s wedding, sharing his fears of familial rejection and pondering why he is yet to find a significant other.

The following year, Brian’s bond with Tex evolves, and he decides to take him on as a client, offering a financial retainer. The Beatles continue their success through 1966, but a disastrous tour of Asia, alongside the uproar stirred by John Lennon’s controversial statements about Jesus, prompts the band to cease touring. The night of their final concert proves to be a turning point, as Tex, feeling neglected, steals Brian’s suitcase, which contains $20,000 and a cache of pills. This act of betrayal, combined with the tumult of the Beatles no longer touring, drives Brian into a deep emotional spiral, resulting in a nervous breakdown.

In 1967, the Beatles are invited to participate in Our World, heralded as the first-ever global television broadcast. Brian suggests they craft a new song carrying a hopeful message to uplift spirits in a troubled world. Unfortunately, tragedy strikes when Harry passes away, shattering Brian, although Queenie reassures him that his father always harbored pride for him, even if he never expressed it openly. Observing familial moments at the funeral stirs sorrow within Brian as he reflects on his own longing for a family, even as his butler, Lonnie, comforts him by suggesting that his chosen family surrounds him.

As Our World goes live, Brian witnesses the Beatles receive warm accolades from their fans and family, marking a triumphant occasion. Not long after, however, Brian’s life takes a tragic turn as he succumbs to an accidental overdose of barbiturates at the tender age of 32, leaving behind a complex legacy intertwined with the triumphs and tribulations of the Beatles.