Following the understudies' debut, Nagisa has a dream about Atsuko, whilst Yūko ponders about Nagisa and Chieri's potential to be Center Novas. After another performance by the understudies, Tsubasa announces the return of both General Elections, in which fans nominate understudies and successors to participate on a single, and the revival of the Center Nova position, exciting Yūko, who declares she'll be the one to claim it. Whilst resting at a hot spring inn, the DES attack and capture Chieri, Sonata, and Yukirin, whose real name is revealed to be Ayako Kuroki, taking them to the High Court on Kasumigastar where they put them on a live trial broadcast across the galaxy. As the rest of the group plan a rescue attempt, Chieri decides to plead her defense, exclaiming her faith in AKB0048. Spurred on by her words, AKB0048 arrive on the planet and rescue Chieri and the others. Meanwhile, Chieri's father is planning something using the data gathered from the trial.

Following the televised broadcast of the AKB trial, Chieri experiences a sudden rise in popularity. In contrast, despite her high demand for gravure photo shoots alongside the successors and rumors of being chosen in the General Elections, Chieri is unable to find confidence in her current popularity.

As the understudies participate in a pre-election handshake event, Nagisa becomes concerned about Chieri, who has been feeling down since the early result announcement. During the event, Chieri learns of a noodle commercial using footage from her trial to promote their product. Later that night, Nagisa observes Yuko and Minami vowing to compete against each other in the elections before hearing from Mimori about her dedication to her fans. The next day, Chieri meets up with a servant from her family, Yasunaga, who gives her a video message from her father, revealing that his group was involved in her trial and has been promoting her idol career since then. As the day of the elections arrives and the final results are announced, Mimori is ranked in 10th place.

Mimori gives Kanata her thanks for helping her get this far, restating her promise that they will both be successors some day. Meanwhile, Chieri is awaiting the results, having said to Tsubasa that she wants to quit 00 if she is announced as she felt she didn't earn her votes, to which Tsubasa responded that if she is elected, she must tell the fans directly that she is quitting. The next set of places go to Sae, Tomochin and Kojiharu, whose speeches help Nagisa understand what the general elections are all about. Conflicted about what she should do, Chieri enters a panicked state when she is announced in sixth place. However, she overcomes her state to announce her love for her fans, saying that she'll continue doing her best. As the next set of places go to Mayuyu, Yukirin and Sayaka, Nagisa starts to have an unnerving feeling. Second place is awarded to Takamina, who gives her thanks to everyone who helped her get this far. Yuko is then announced as the winner, where she states her true goal is still to surpass Atsuko and become Center Nova. After the ceremony, Nagisa overcomes her fears and vows to face Chieri head on.

The elected members are chosen for a concert on Baltistar, a planet completely under the entertainment ban. Meanwhile, the 77th generation of understudies are chosen to infiltrate a nearby military base undercover in order to investigate reports of important business people visiting the base. As the concert begins, drawing out the DES forces, the understudies begin their mission and start gathering intel. During their investigation, Nagisa, Yūka and Makoto discover a hidden casino where elite members gamble on how long the concert will last. As they attempt to investigate further, Makoto inadvertently blows their cover. However, due to an apparent stroke of luck, they manage to escape to a garbage disposal and report their findings to Tsubasa. The girls decide to target the nuclear reactor hidden somewhere in the base so they can shut down the casino and escape, with Orine's team using a stolen mech to help them. As Makoto laments her usefulness, Higashino, the DES guard that helped them escape, gives her his support and helps her to shut down the reactor, gaining her own Kirara in the process.

After the unexpected election of certain members, fans and members of 00 alike excitedly speculate on the possibility of succession. Yuko, who announced her desire to become the Center Nova, frantically attempts to assess the shine of Nagisa and Chieri, one of whom she suspects will become the 14th Generation Maeda Atsuko.

With the succession of a trainee confirmed, a succession concert is schedule. The trainee prepares for her succession in the underground shrine of Akibastar.

Inspired by Mimori becoming the 8th Generation Shinoda Mariko, the successors and trainees shine even brighter. "When a Center Nova is born, the other members shine."

News of the surprise DES attack on Akibastar reaches the distant planet Lancastar, worrying Mamoru. Also, Nagisa's father is transferred to a department completely unrelated to entertainment at Zodiac's orders. What is their goal?

Thanks to Michan's actions, the Flying Get narrowly escapes the DES. However, its systems are badly damaged, and the ship is unable to move.

Arriving on Sagittariusstar, Chieri and Nagisa meet up with Yasunaga who takes them to Chieri's home as he attempts to set up a meeting with Chieri’s father. In the meantime, Chieri tells Nagisa about how she discovered AKB0048.

The plan to take back Akibastar will be carried out soon. Nagisa and the others focus on their lessons. However, Chieri is still unable to recover from the shocking event she witnessed on Sagittariusstar.

Due to the mind control actions of the DES, the people who were once fans of 0048 now hate Nagisa and the other members.