Neil McCormick and his brother Ivan dream of rock stardom while growing up in Dublin. Attending the same school as Paul Hewson (later known as Bono) and his band, U2, the brothers decide to form their own group, Shook Up!, hoping to rival U2's success. However, Neil's ambition and frequent missteps result in a series of unfortunate events that consistently leave Shook Up! struggling in the shadows of U2's meteoric rise. As U2's fame grows, Neil's resentment and frustration toward Bono intensify, fueling his relentless yet misguided determination to prove he and his brother can achieve rock greatness on their own terms.

After a move to London, the brothers face numerous setbacks, including missed opportunities, financial hardships, and internal band conflict. Their journey in the competitive music industry is fraught with challenges, and Neil's decisions often jeopardize the band's success and his relationship with Ivan. Despite their efforts, Shook Up! is consistently overshadowed by U2's unparalleled popularity, driving Neil to the brink of desperation. As the brothers' dreams of fame and success wane, their personal and professional lives are pushed to the breaking point, leading to a critical turning point in their quest for musical recognition.