When Koyuki accepts Ryusuke's invitation to see his band perform live, he unwittingly sets down a path of self-discovery. But what Koyuki finds both disturbs and intrigues him, as the youngster uncovers the best and worst aspects of human nature. And though his world begins to expand, self-doubt and uncertainty threaten to send it collapsing in on itself.

Koyuki hangs out with Ryusuke and finds out more about music, and meets his sister, Maho, who later takes Koyuki to see Beck, her brother's dog.

While Koyuki takes his first tentative steps toward learning guitar, Maho suggests that he'd be the perfect lead vocalist for Ryusuke's new band. But an accident threatens to shatter Ryusuke and Koyuki's friendship forever, as well as putting an end to Koyuki's musical aspirations-until help comes from a very unexpected source.

Koyuki tries to memorize the scales at Saitou's place. Later we can see Koyuki talking with the bullies and then scolded in the teacher's office. Maho meets with him, and at Saitou's place, Koyuki tells her why he started to work for the old man. This marks the first appearance of Ryusuke's guitar, "Prudence" ("Lucille" in the Japanese original), notable for the several bullet holes it bears.

Dying Breed performs in concert live in Japan, with Koyuki unexpectedly guest singing. Later on, Koyuki and Izumi meet again and she invites him for night-swimming, much to Maho's chagrin when she finds out. Meanwhile, Ryusuke finds out that somebody close to him has died.

Ryusuke (along with Beck and Prudence) get kidnapped by Sykes, who takes him to meet his uncle, the bluesman John Lee Davis, who wanted to know who had stolen Prudence. Upon meeting Davis, one of his musical inspirations, Ryusuke has a jam session which overwhelms his idol, so much so he convinces Sykes not to kill him. So, four days after his kidnapping, Ryusuke is returned, badly beaten, but alive (but Sykes keeps Beck and Prudence with him). As he asserts the situation to Taira and Chiba, Koyuki and Saku, who were looking after the fishing pond for Ryusuke, are visited by one of the managers of the Greatful Sound Festival, Kazuo Sato, who is ecstatic to meet Koyuki after seeing him sing in the Dying Breed's tour movie. Koyuki later gets the chance to see himself on the silver screen, along with Maho.

Ryusuke talks with Chiba and Taira about his talk with Sykes. Back at school, Hiromi talks with Koyuki and Saku about playing guitar. Ryusuke wants to make a new CD, and proposes they write new songs for it. Later on, Ryusuke, Taira and Saku go to a live show in which Chiba is performing with another band, knowing that he is doing so just out of worry that Beck may not take off as quickly as he would like. That night, when Maho comes over to Koyuki's house again, Page (which Koyuki is taking care of for Saito, who is on a business trip) flies off and they go looking for him, while they start commenting on how common Koyuki thinks himself to be, though Maho has quite an opposite opinion. Later at home, Koyuki starts strumming an improvised melody on his guitar, so beautiful that it brings Page back and makes him sing to it. The next night, while Sykes takes Ryusuke for their business meeting (where he will impose his conditions for Beck to perform at Greatful Sound), Koyuki goes further into his self-thought song (which will become "Slip Out"), eventually showing his progress to Ryusuke. Despite the amateurism of the production, this song gives Ryusuke the push he needs to take Beck into Greatful Sound.

After the band seems to break up before their time on the third stage, the band is slowly reforming just in time to play their hearts out for the growing crowd. Ryuusuke has returned after being given Prudence to play on and Chiba races back to the third stage after thwarting his kidnappers. Meanwhile, the worsening weather forces interruptions at the other two stages, frustrating Eiji and angering Sykes.

As Beck's set finishes up, the reality that it's Beck's last performance finally sets in. Koyuki and Maho realize their love for each other and time goes on and the members of BECK move on with their lives. One month and a half later, Koyuki gets an unexpected phone call from Kazuo Sato, who takes her to a meeting with none other than Sykes, who had seen him perform at Greatful Sound and expresses his desire to produce a solo album for Koyuki, but he politely refuses. With Ryusuke missing, Chiba wanting to assemble his own ramen shop, Taira in another band and the news that Saku will transfer to another school, Koyuki's uneasiness returns day by day, even more so after he and Saku part ways.