Episode 01 - Suddenly an Idol

Suddenly an Idol (アイドルは突然に) is the first episode of the Aikatsu Planet! TV series. It aired on January 10th, 2021.

Summary
Mao Otoha is a first year student who is good at ballet and attends Seirei Private High School. One day, she is suddenly asked to act as Hana, the top idol of Aikatsu Planet and the object of everyone's admiration. Receiving the help of the beautiful Dressia Aurora Pegasus, this girl's brand new Aikatsu! begins!!

Plot
On her way to school, Mao Otoha is shopping for hair accessories. She ends up not being able to choose what to buy as she meets up with her best friend, Shiori Motoya.

The pair witness a crowd forming nearby, where a big screen is broadcasting an idol's performance of "HAPPY∞Aikatsu!". Mao is enamored by the idol, whom Shiori identifies as Aikatsu Planet's Hana. A top idol, Hana's user Meisa Hinata is also quite popular.

Shiori reminds Mao that they need to go and heads off. Mao runs to catch up and bumps into a mysterious girl with a backpack and suitcase, sending them both to the ground. Mao apologizes and helps the girl with her belongings, picking up a small card that had fallen out of her pouch.

The two go their separate ways, but turn around to look at each other one last time. In a voiceover, Mao says that unbeknownst to her, her destiny had begun to move.

At school, Mao is asked by a group of other students to teach them to how to dance for a hip hop performance at an upcoming school festival. Although Mao used to do ballet, she is initially reluctant as she's never actually taught anyone before. As they continue to plead with her, Mao eventually decides to give it a try.

Mao leads the group in practicing the dance and easily picks up the choreography. Shiori is amazed, as hip hop and ballet are different styles. A woman is shown passing by and notices Mao, captivated by her dancing. Ruli Tamaki calls out to the woman, revealing her to be manager Izumi Watanuki. Izumi hands Ruli the documents for her next fashion event. Ruli asks Izumi for her opinion on what dress she should wear, and Izumi suggests Glossy Ruby.

Ruli notices Izumi's interest in Mao, and the manager explains that Mao reminds her of how Meisa used to be. Suddenly, Izumi receives an urgent call from her assistant Itsuki Segawa. Segawa reveals to Izumi that Meisa has disappeared, leaving behind her Idol License, AiPla Phone and a note saying "Thank you for everything up until now. Goodbye".

Izumi says that they have no choice but to cancel Hana's schedules, but Segawa expresses concern over her next battle stage with Q-pit, as tickets have already sold out. Segawa asks if Ruli can act as a replacement for Meisa, but Izumi says that Ruli is too different. Then, she recalls Mao.

As Mao and Shiori are leaving school, Izumi comes up to them and asks to talk, bringing the girls to a cafe. They are surprised as Izumi explains the situation and implores Mao to take over as Hana for the upcoming battle stage. When Mao questions why her, Izumi says that feeling she had when she first saw Meisa dance is the same as when she saw Mao earlier that day.

Izumi expresses her love for idols, admiring them for their passion and saying that watching them motivates her to work harder - they have the power to bring positivity and courage to others. After some encouragement from Izumi, Mao resolves to take on the challenge. Acting as her support, Shiori oversees Mao's training as she starts her idol activities in preparation.

The day of the performance, Mao and Shiori head to Starlet Promotion, where Izumi introduces them to Segawa. Izumi gives Mao Meisa's Idol License and AiPla Phone, instructing her how to transform into Hana. Mao inserts the License into the Phone, manifesting a mirror that shows Hana as Mao's reflection.

Mao places her hand on the mirror, changing into Hana as she enters the world of Aikatsu Planet. Izumi and Shiori follow her in, with Izumi giving Hana a Swing containing the dress she'll be using. However, Izumi says that the dress is still incomplete, and that Hana needs to infuse it with the power of a Dressia. She explains that Dressias are beings that hold the key to winning stages, and sends Hana into a forest in which only idols are allowed to go borrow a Dressia's power.

Hana struggles with finding a Dressia to complete her dress until she sees a pegasus drinking from a pool. She introduces herself and asks for the pegasus to lend her power. Wanting to become Hana's dress as well, the pegasus enters her Swing and completes the coord.

The battle stage between Aikatsu Planet's #1 and #2 - Hana and Q-pit - finally begins. Backstage, Q-pit goes up to Hana and firmly states that she has no intentions of losing today's battle, as if she wins, their rankings will switch and she will become number one. Izumi and Shiori arrive, telling Hana to go on standby. Izumi says that while Q-pit is a formidable opponent, with accurate performance and virtually no weaknesses, Hana should focus on having fun and being herself.

Resolving to enjoy herself to the fullest, Hana brings out Aurora Pegasus and changes into her coord. Entering the stage, she and Q-pit perform a duet of "HAPPY∞Aikatsu!". The results are soon announced, with Hana managing to beat Q-pit. Q-pit congratulates Hana on her win, but is puzzled when Hana addresses her as "Q-pit-san".

Q-pit and another idol are seen watching as Hana celebrates with Shiori and Izumi. Q-pit's companion expresses frustration over the results of the battle. However, Q-pit is more concerned over the fact Hana used a Fairy Dressia when she's always used Flower types, which are weak to Q-pit's preferred Horoscope types.

The week rolls by, and Mao and Shiori are on their way to school and see Mao's performance as Hana being broadcasted on the big screen. Shiori playfully asks who acted as Hana on that stage. Mao replies that it's a secret, and the two girls run off.

Characters

 * Mao Otoha/Hana
 * Ruli Tamaki
 * Shiori Motoya
 * Q-pit
 * Ann
 * Meisa Hinata
 * Izumi Watanuki
 * Itsuki Segawa
 * Keito Kirihata
 * Shō Kurosaki
 * Ryōka Dōba
 * Aurora Pegasus

Trivia

 * Episode Title Reference: "Sudden Love Story" (ラブ・ストーリーは突然に) by Kazumasa Oda
 * This marks the series premiere of the Aikatsu Planet! TV series.
 * This episode premiered on the birthday of Nono Daichi from the original Aikatsu! series.
 * This episode marks the debut of main characters Mao Otoha, Shiori Motoya, Meisa Hinata, Ruli Tamaki, Hana, Q-pit and Ann, along with secondary characters Izumi Watanuki, Itsuki Segawa, Keito Kirihata, Shō Kurosaki and Ryōka Dōba.
 * The opening theme song "Bloomy＊Smile" is first used in this episode.
 * Aurora Pegasus and Noble Leo make their debut in this episode.
 * Luxe Sunflower, Marine Pearl, Glossy Ruby, and Hip Hop Break make cameo appearances in this episode.
 * "HAPPY∞Aikatsu!" makes its debut as an insert song in this episode.
 * This is the first time that an opening appears as an ending.
 * The ending sequence mistakenly credits Ruli and Shiori despite not appearing.