Teen Regime

• Fūju Kamio as Aran Maki (真木亜蘭)[2]

Haru as young Maki; Ō Aoki as 10-year-old Maki

17-year-old high school student chosen by Solon as the Prime Minister of experimental city Ūa. He was raised by a single mother and, after his mother passed away, his grandmother, whom he had to take care of. After his grandmother passed away, he learned to program, and also participated in an online forum for high schoolers to discuss politics. This upbringing influenced him to become a politician, though the death of his friend Yuki Shirai, the victim of the cover-up of illegal donations, was a great influence. After his AI Snow goes rogue, he was dismissed as prime minister, though he later participates in the revived lantern festival through the metaverse while studying abroad. Kamio said that Maki is mysterious, and that "at first glance looks like he's not a high school student, but he sometimes acts like [one], and it's a role hard to grasp."[3]

• Anna Yamada as Sachi Sagawa (茶川サチ)[4]

17-year-old high school student who becomes the Prime Minister's Aide. After meeting Maki through the forum, she earnestly prayed for him to become prime minister, as she had been rejected from the program. She thought she caught Maki's attention after making a presentation on a goodwill point system in the forum, but it is later revealed that it was because of her resemblance to Yuki, who died at 17. She moves to Ūa with her family after becoming his Aide and continues to live there after Maki's dismissal.

• Gen Hoshino as Kiyoshi Taira (平清志)[1]

Deputy Chief Cabinet Secretary, a politician called "the next generation prime minister candidate". He is the project manager of Utopi-AI but was rejected as a cabinet minister. In the Washida cabinet, dominated by elderly politicians, he is popular as a young minister. He nursed his mother during college and entered politics while passing the bar exam. Initially, he threatened Washida with the diary containing evidence of illegal donations and tried to become prime minister, but after Maki comes clean about Snow becoming out of control, forcing Washida to resign, he becomes Prime Minister of Japan three years later.

• Yuumi Kawai as Suguri Saiga (雑賀すぐり)[3]

22-year-old Minister of Finance and Economy. She has an MBA from Gritz University in Iowa, and speaks English, Chinese, Spanish, and Russian. When Saiga was 15 years old, she went to the United States out of disappointment with Japanese society's lack of investment in its future and young people.

• Ayumu Mochizuki as Kan Hayashi (林完)[3]

22-year-old Minister of Health and Welfare. He used to be an in-house lawyer. Since he studied design at a vocational school and is qualified as a patent attorney, Hayashi designed the user interface for Ūa's resident system. He has a younger brother who uses a wheelchair due to an accident, so he thinks of actively spreading accessible design throughout the city, and also wants to create a cultural city that supports artists.

• Shota Sometani as Teru Washida (鷲田照)[3]

25-year-old Minister of Environment and Development. He is the grandson of Tsuguaki Washida, the Prime Minister of Japan, and was born in Aonami City. Though initially supporting conservative elderly politicians, after succeeding Maki as Prime Minister, he introduces citizen observers to replace the abolished city council and strives to create make Ūa a city where all generations can be happy.

• Marika Matsumoto as Saki Yamaguchi (山口早希)[5]

Journalist. Taira's friend since they were students. She pursues the truth behind suspicions of Washida receiving illegal donations, and after receiving Yuki's diary from Taira, reports the truth.

• Akira Emoto as Tsuguaki Washida (鷲田継明)[5]

Prime Minister of Japan. Founder of Project Utopi-AI; though he professes that he is in charge of the project, he pressures Taira to make him responsible if the project fails.

• Anna Yamada as Snow (double role)

Voiced by Moeka Shiotsuka

"17-year-old Yuki", an AI installed in a secret basement accessed from Maki's private room in the official residence. She is modeled after Maki's friend, Yuki Shirai (白井雪), who passed away 7 years ago, was turned into an AI, and grew up to be 17. She looks exactly like Sachi except for her long hair.

• Tetta Sugimoto as Masaki Sagawa[5]

Father of Sachi and Kisuke. He was a house husband after becoming unemployed due to restructuring. After moving to Ūa, he posts photos of his favorite dishes on social media, which leads to him getting a job at a cookware manufacturer.

• Naomi Nishida as Tae Sagawa[5] (née Tae Morimoto)

Mother of Sachi and Kisuke. She is a devoted fan of Taira. Though she was a junior high social studies teacher, due to reforms she is subject to staff reductions. She accepts retirement because her husband got a job, and her son enjoys classes taught by AI.

• Kenshirō Katō as Kisuke Sagawa

Sachi's younger brother. When he lived in Utsunomiya, he was bullied at elementary school, did not attend school, and was immersed in online games at home. After moving to Ūa, he shows interest in politics and his studies.

• Ayata Toshiki as Taiki Sagawa

Grandfather of Saki and Kisuke. After his wife Kiyo's death, he lives alone while being cared for by Masaki. After moving to Ūa and in with his son, he tries first and foremost to note cause trouble for the family.

In 2022, planning for the Saturday drama slot, broadcast on NHK World-Japan, started. Through research by overseas producers on what was expected of a Japanese drama, the motifs of artificial intelligence and science fiction emerged.[6] Reiko Yoshida was contacted for the script, and she came up with the plot of a "17-year-old's empire" where a young Prime Minister builds a nation of young people and fights against an aging society.[7] Producer Ayumi Sano suggested combining the motif of AI with Yoshida's plot for the story of a 17-year-old using AI to run the government. The production team then worked on researching and developing the plot.[8] Though producer Kei Kurube found the political aspect of the plot difficult, he decided he wanted to create something new.[6]

Yoshida initially conceived a dystopian plot, but after meeting with Sano, it was changed to Maki resigning as Prime Minister and his reforms remaining in Ūa. After the plot was changed from a dystopia, main director Takegoro Nishimura and production designers decided to make Ūa "a place that everyone wants to go to".[9]

The collaboration between Sano, a commercial producer, and NHK, a public broadcaster, was due to Sano having retired from TBS TV, then working as a freelancer. Though Sano became an employee of Kansai Telecasting, he participated with his company's understanding to fulfill his personal goal to "challenge what only NHK can do". On hiring Yoshida, who mainly works on anime, for the script, Sano said he thought, "If I'm going to make science fiction, I'd rather work with a scriptwriter in a different genre than the serial drama scriptwriter I usually work with."[7]

Sano recruited Ryoma Hattori, part of NHK's video design department and thus usually not involved in dramas, to brainstorm gadgets like Utopi-AI's user interface, the branding of the city, and to make everything feel like a live-action.[8]

Kiyoshi Taira, played by Gen Hoshino, did not initially exist in the plot, but Sano wanted a character that fought between the young and elderly. According to Sano, once the bubble generation retired from the film industry, he thought it was finally time for his generation to make a comeback, but it quickly became the age of "raising the digital natives of the next generation"; his generation was "taken off the ladder" and Sano wondered how people would react to a "middle-management-like person".[10]

Hario Radio Tower in Sasebo, filmed as AI Solon's towers

The three towers of Solon were filmed at Hario Radio Tower in Sasebo, Nagasaki, and there was also filming in the telegraph room of the tower.[11] The directors looked for "cities, towns, and villages that are experimenting realistically" and "beautiful landscapes where the science fiction world and life co-exist". They described the towers as "beautiful no matter where you look at them, and no matter where you look at them, they are strange". After projecting it on a monitor, it was selected for its impact.[12]

The facility where the Sagawa family prepares to move into Ūa was filmed at the Yokosuka Museum of Art.[13] The Aonami City Hall was filmed at the town hall in Higashiizu, Shizuoka.[14] Mamiana Shopping District was filmed in various parts of Japan, including Tonō Market in Sasebo, Nagasaki.[15] The history of the filming locations, such as the telegraph room being built during the Taishō era, and the stores being built using an air raid shelter, were incorporated into the plot.

Shooting was done without the cast knowing what the actual scene would look like,[8] such as in scenes where the smartglasses where involved.[16] Yamada, in the role of Snow, an AI, acted alone while filming, setting the timing for when Snow appears on the monitor to correspond with Maki.[8]

• Galaxy Award (Broadcast Critics Round-Table Conference): June 2022 TV Category Monthly Award[20]