When a despondent fourteen-year-old named Koyuki rescues a peculiar dog named Beck from local bullies, his mundane life takes a dramatic turn. Beck's owner, the talented guitarist Ray, introduces Koyuki to the vibrant world of rock music, inspiring the young boy to pick up the guitar himself. With the addition of Ray's sister Maho and other allies, Koyuki and Ray embark on a thrilling journey to create the ultimate rock band, BECK. Through trials and triumphs, the band navigates the competitive music scene, gradually building their reputation throughout Japan.