Today, we crossed our borders and transformed our worlds.*
Borderless is a 2021 Japanese mystery television series, originally launched on the streaming service Hikari TV. It was adapted from a novel of the same title by Tetsuya Honda. It is the first collaboration of selected members of Nogizaka46, Sakurazaka46, and Hinatazaka46 in a drama, and the novel was actually written with that in mind (or at least for the latter two, which were formerly one group called Keyakizaka46). It tells the story of four unrelated groups of people, the borders between whose worlds would unexpectedly fade away: classmates Nao Mori (Hikaru Morita) and Kiri Katayama (Kyoko Saito); Haru and Kei Yatsuji (Risa Watanabe and Hiyori Hamagishi), daughters of a karate master; musically-inclined sisters Kotone and Kanon Ichihara (Yui Kobayashi and Seira Hayakawa); and sheltered rich kid Yuki Matsumiya (Sakura Endo).A sequel to the novel, titled Actress, was released in January 2022, and was also adapted into a television drama in 2023.
Borderless provides examples of these tropes:
- Asshole Victim: Matsumiya has destroyed many people while building his business and has his former mistress assaulted to prevent her from humiliating him by seducing his daughter.
- The Atoner: Haru vowed to become Kei's eyes after Kei lost her sight in an accident while they were together as children.
- Badass Creed: The Yatsuji Badass Family live by their dojo's creed.
- Becoming the Mask: Maya originally only seduced Yuki to humiliate Matsumiya, but grows to genuinely love her and takes extreme measures to reunite with her.
- Bland-Name Product: The Matsumiya pharmaceutical company (which employee's cufflink Kiri found at the crime scene in the first episode) produces bland name products of Pocari Sweat and Calorie Mate, which makes it that universe's version of Otsuka Pharmaceutical.
- Central Theme: All the main characters have their own stories but improve their lives in some way by crossing the "borders" into each others' lives. Also in a meta sense since this is the first collaboration of three related girl groups.
- Ordinary High-School Student Nao discovers her knack for investigation and eventually becomes a police detective through hanging out with the loner Kiri, who's also helped in her writing by Nao, even more so after she can tag along in her criminal investigations.
- Haru is trapped in guilt after her negligence caused her sister Kei's blindness, but their ordeal shows that Kei is capable of taking care of herself, and she encourages Haru to live her own life.
- Kotone and Kanon make up after Kanon confesses her jealousy of her sister, and both become free to continue their lives without emotional baggage. Kotone and Yuta get a Wedding Finale with Kanon's blessing.
- Yuki breaks free from her Gilded Cage through her connection with Maya, although it involves her killing her own father.
- All the main characters except Yuki also become friends after surviving the events together.
- Childhood Friend:
- Saeko is Nao's childhood friend and occasionally tags along in her and Kiri's investigations, especially when they need her boyfriend's car to travel.
- Yuta is the Ichihara sisters' childhood friend and the three of them form a Love Triangle.
- Distant Finale: The final episode is set around five years after the main story, when the main characters have become working adults.
- Foreshadowing: The very first scene is Yuki smeared in blood. Kiri also muses in a later episode that the Matsumiyas's sheltered daughter might have killed her own father.
- The Glorious War of Sisterly Rivalry: Kanon is in bad terms with her older sister Kotone, not least because she abandoned her musical aspirations and quit playing the piano. Actually the bigger reason is because Kanon's interested in their Childhood Friend Yuta, but he's only interested in Kotone.
- Handicapped Badass: Kei is nearly blind but still knows karate, like her sister and father. Her blindness becomes an advantage when she subdues Maya in the dark cafe.
- I Should Write a Book About This: Kiri establishes a theater company in the epilogue and produces a stage play based on Yuki and Maya's love story. Even though she disapproves that Maya hurt many people in her search for Yuki, she gave them a happy ending in her version nonetheless.
- It's for a Book: Kiri takes Nao to the murder scene near their school and is terrifyingly enthusiastic while picturing how the murder happened, and Nao accidentally sees her notebook containing various murder methods and facts about death. Kiri is actually collecting data for a mystery novel she's writing.
- Lonely Rich Kid: Delicate and Sickly Yuki Matsumiya spends her days reading alone on her mansion's veranda.
- Meaningful Name:
- Nao is a homophone of "simple" or "ordinary" (直). Mori also happens to be part of her actress's name.
- Kiri is a homophone of "cut" (斬り) and she studies murder.
- Musician sisters Kotone and Kanon have the kanji "sound" (音) in their names.
- Mistaken Identity: Mr. Yatsuji works as caretaker to the unused Matsumiyas' mansion. When Maya visited the mansion to reunite with Yuki, she mistook Kei as Yuki and believed Mr. Yatsuji was tasked by her parents to keep Yuki away from her, leading to her invading their home and attacking Mr. Yatsuji. The Matsumiyas did return there for Yuki's twentieth birthday party and Yuki did wait for Maya outside the house as they had promised, but she got into an argument with her father and ended up killing him in a fit of rage. Maya arrived after her mother took her away and found his corpse near her book, deduced what happened, and took away and disfigured the corpse to buy time for a cover-up, and later to take the fall. Her mistake is thinking that Yuki's mother only made it look like they'd left and they were actually still staying there... or maybe that was just an excuse to go on a spree and get herself arrested in Yuki's place.
- Ordinary High-School Student: Nao considers herself one, but Kiri sees a "different", pure kind of ordinariness in her.
- Postmodernism: Kiri and Nao discuss the position of authors as the Gods of their own works. The novel Kiri is writing has a similar story to Haru and Kei's ordeal, while Haru and Kei watched a television drama when they were younger which story is similar to Kotone and Kanon's lives.
- Rape as Drama: Maya reveals that Matsumiya had her physically and sexually assaulted to scare her away from further associating with his daughter. As Maya puts it, no ordinary woman can endure what he did to her, also implying that it's the reason she now lives as a man.
- "The Reason You Suck" Speech: Kei gives one to Maya after she reveals that her recent assault spree was ultimately caused by her willfully misidentifying Kei as Yuki, desperately wanting to believe that Yuki is waiting for her rescue.
- Significant Birth Date: Yuki's birthday is on February 29, so her birthday is only celebrated every four years and is also the day of the murder.
- Sinister Car: After she discovered Kiri's murder notes and found threatening messages in her textbook, Nao is followed by a mysterious red sportscar on her way home from school. It's actually Saeko and her boyfriend pranking her.
- Stalker with a Crush: The threatening messages sent to Kiri are a Red Herring since they're actually from one of her teachers who wants her to notice him, who also has a shrine to her in his apartment.
- Taking the Heat: In addition to her crimes of assault, Maya goes to prison for murdering President Matsumiya, who was actually killed by his daughter and her lover Yuki in a quarrel. Kiri suspects that this is the case, but chooses to move on with her life and let the police handle it.
- A Taste of Their Own Medicine: Maya takes Matsumiya's corpse to the abandoned locker room where he had her assaulted by several men, and savagely disfigures his face beyond recognition there.
- Tragic Keepsake: Maya carries the novel she used to read with Yuki during her hunt and drops it during The Reveal, and Nao keeps it. Nao later gives it to Yuki's mother and asks her to give it to Yuki, which she does.
- Wham Episode: Episode 8 is where Maya reveals her love story with Yuki and why she attacked Haru and Kei's father. Episode 9 is the real Wham episode, where it's revealed that despite her violent crimes, Maya did not kill Matsumiya, but she takes the heat for Yuki.
- The Worf Effect: The person who invaded the Yatsujis' home quickly subdued the karate master Mr. Yatsuji, and he urges his two daughters to run away and find help rather than fight back.
