"Be Rockin'" centers on a group of high school students who form a rock band, navigating the challenges of adolescence, friendship, and their shared passion for music. The protagonist, Haruto Saito, is a reserved yet talented guitarist who struggles with self-doubt and the pressure to live up to his late father’s legacy as a renowned musician. After transferring to a new school, Haruto encounters Rina Takahashi, a spirited vocalist with a bold personality, and together they decide to form a band. They are joined by Yuki Nakamura, a skilled but perfectionist drummer, and Akira Tanaka, a laid-back bassist with a knack for improvisation.

The narrative explores the band’s journey as they compete in local music competitions, face rival groups, and confront personal insecurities. Each character’s backstory is gradually revealed, adding depth to their motivations and relationships. Haruto’s internal conflict over his father’s expectations and his own aspirations drives much of the emotional tension, while Rina’s determination to prove herself as a vocalist despite her unconventional style creates a dynamic contrast. Yuki’s struggle with balancing her high standards and her fear of failure, alongside Akira’s carefree yet deeply loyal nature, rounds out the group’s dynamic.

As the band gains recognition, they encounter external challenges, including industry pressures, rival bands, and the complexities of balancing their dreams with academic responsibilities. The series also delves into themes of identity, perseverance, and the transformative power of music, as the characters grow both individually and as a cohesive unit. The story culminates in their participation in a national music festival, where they must confront their fears and insecurities to deliver a performance that reflects their growth and unity.