High schooler Akira was raised as the heir of Kikunoyu, a sento bathhouse run by his grandfather and mother. He always had dreams of becoming a hero. But he quit baseball, which he'd been playing since he was young, and spent his days going to karaoke after school with his childhood friend Kacchan. One day, Kacchan receives an email from the idol talent agency sMiLea Production on a recommendation from the legendary idol Anela. Although Akira has no relation to it, it seems that he might be involved...

Akira is unable to hide his surprise that he was singer KIKUNOYU, but decides to try his hand at being an idol. When visiting the agency office, he is told he'll be in an idol group with singers EVAN (Banri) and Suzu (Chihiro). On their way home, Banri, wearing a mask and sunglasses and dressed suspiciously from head to toe, suddenly gets frightened and hides when Chihiro reaches out for his mask. There seems to be a reason for his suspicious getup──?!

At the live performance, Akira is moved by the presence of Daiki, who looks like the main character of Akira's favorite hero anime, "Crossfire." Revved up, Akira and his group get inspired for their lessons, but the dance lessons particularly seem hopeless. Later, it's decided that the three of them will get to participate in a commercial shoot as LEGIT's backup dancers. Although there's not much time before filming begins, LEGIT gives them one-on-one dance lessons. Akira, who fretfully practices yet makes little progress, begins feeling impatient and makes a proposal to Banri and Chihiro.

Akira's group is relieved to make it through the commercial shoot without any problems when Lin immediately informs them that their debut has been set. At the same time the three are busy with shoots and interviews, Anela features in an up-close and personal program focusing from now up until their retirement. Various thoughts and memories come back to the surface, including the day Lin and Maoto decided to retire and the establishment of sMiLea Production.

On the day of Akira, Banri, and Chihiro's group unveiling, a typhoon forces them to cancel their live outdoor performance. Instead, the three who want to express their gratitude directly to the fans who stood by them as online singers propose a crowdless online live stream. But Lin was adamantly against it. He wanted a properly prepared event for the three-man group, but with the help of LEGIT and JAXX/JAXX, he changed his mind. The live stream somehow begins to take shape thanks to everyone's cooperation, but the power goes just before starting...?!

As PROTOSTAR, Akira, Banri, and Chihiro successfully completed their live debut. But for some reason, Chihiro seems conflicted. In actuality, Chihiro is the eldest son of a famous Japanese dance master. Chihiro, unable to get into the swing of practice, is severly troubled that he cannot tell his father he is an idol nor can he tell his friends the situation. Worried about Chihiro who keeps skipping lessons, Akira and Banri visit Chihiro's house──?!

With Chihiro's problem solved and their bond deepened, PROTOSTAR arrives in Hawaii together with LEGIT, JAXX/JAXX, and their leaders, Lin and Maoto. Actually, it was for a magazine photo shoot featuring the idols affiliated with sMiLea Production. Still, Akira, who was overseas for the first time, led the way putting everyone in high spirits. Each of them had a good time eating and sightseeing during the shoot. But on the flight home, they suddenly realized Banri was missing...!

A few years back, Homare, Izumi, Jun, and Kanata lived together in a share house while working as an idol group, but they were unexpectedly fired. While in a slump, they found and helped Gakuto who had apparently collapsed from hunger and was lying on the side of the road. The four were moved by Gakuto, who came to Tokyo to make music, and his singing. Later on, Izumi is invited by Homare and the others to join a band. But try as he may, he worries about the future, unable to take the first step forward...

JAXX/JAXX's nationwide tour finishes, and during the after-party, Rin and Maoto announce that they have decided to hold sMiLea Production's first-ever joint live performance. While PROTOSTAR is excited for their first concert with a live audience, and LEGIT and JAXX/JAXX get fully motivated, it's decided that they will all perform a song written and composed by Maoto at the joint live show. While the important role of the group's lead has yet to be chosen, a suspicious reporter reaches out to Daiki──!

Confusion hits everyone at sMiLea Production when an article in a weekly magazine states that the person who forced Lin to retire from being an idol was Daiki. The group's lead still has yet to be decided, and there are rumors that the joint live performance will be canceled. But while everyone gets increasingly anxious, only Akira continues to believe in Daiki. Akira does his best to support LEGIT's work and make the joint live performance a reality with persistence and a positive attitude. One day, Akira runs into Daiki at the same school he attends for supplementary lessons...!

Akira's determination to never give up and his unfailing faith in Daiki is conveyed through a game of baseball, and with Daiki's recommendation, Akira becomes the group's lead. With each of their thoughts and feelings connected and united as one, sMiLea Production's joint idol live performance finally lifts its curtains for showtime──!