‘City Hunter’ Movie Recap & Ending Explained: What Is The Blue Serum?

Not all heroes wear a cape, especially in this Netflix adaptation of the manga City Hunter. Ryou Saeba is a crime-fighting freelance detective who goes through the painstaking journey of finding the man behind the murder of his partner. When Ryou is not solving cases or fighting crimes, he is flirting with women, or at least leering at them. While I haven’t read the manga, I have heard of the unnecessary ‘fanservice’ in the source material. Fortunately, Netflix has tried to tone down Ryou Saeba’s sexist remarks and perverted behavior.


Spoilers Ahead

How does Hideyuki die?

Set in the bustling metropolis of Tokyo, freelance detectives Ryou Saeka and his partner, Hideyuki Makimura, a former police officer, navigate the city’s grimy underbelly in pursuit of justice. Their latest adventure unfolds when a woman seeks their assistance in locating her missing sister, Kurumi. Ryou and Hideyuki track down Kurumi at a local gang’s hideout. However, what ensues is a comical chase as Kurumi, mistakenly believing the detectives mean her harm, flees in a panic. In a surprising turn of events, Kurumi unveils supernatural abilities, evading capture but inadvertently dropping two vials of a mysterious blue serum in her haste.


Elsewhere, Hideyuki plans to reveal the shocking truth to his younger sister, Kaori, that she was adopted. But their family dinner takes a tragic turn when a man viciously attacks, driving his truck into the restaurant where they are dining. While Hideyuki narrowly escapes being crushed, the assailant ultimately stabs him to death. With his dying breaths, Hideyuki entrusts Ryou with the care of his sister, Kaori.

Why does Ryou avoid working with Kaori?

Though Ryou was refraining from expressing his true emotions, he was equally affected by his friend’s demise. To deal with the grief, he went back to his hedonistic life as a playboy. When Kaori approaches him for help with bringing her brother’s culprit to justice, Ryou turns her down. Initially, it seemed like he didn’t care and that they ought to move on. Even though it seems very ignorant of Ryou to say something like this regarding the death of his own friend, he is simply following his promise to Hideyuki about taking care of his sister. Ryou knows that the world of a detective can be a dangerous one, and letting her put herself out there would put her in danger. After multiple pleas and requests, Ryou finally makes up his mind about letting Kaori investigate Hideyuki’s death, and to do so, they must find Kurami. 


What Is The Blue Serum?

The blue serum contains a drug that gives superhuman strength and agility to its users. However, this wonder drug comes with a devastating price: it drives individuals to the brink of insanity before ultimately leading to their death. Despite these lethal side effects, the serum has gained a dangerous popularity on the streets, with many willing to risk everything for a taste of its extraordinary powers. This compound was developed by Lore, a subsidiary of the pharmaceutical giant Seta. Through a haunting flashback, it is revealed that Kurumi, an unsuspecting victim, was abducted and forcibly injected with the experimental compound. While most test subjects succumbed to the serum’s deadly effects, Kurumi’s survival marked her as an anomaly, a rare exception to the drug’s catastrophic consequences. It is this miraculous resilience that has made Kurumi a prime target for Lero, the very organization responsible for her abduction and experimentation. Driven by nefarious motives, Lero is relentlessly dispatching operatives to recapture Kurumi, desperate to unravel the mystery behind her unique tolerance to the serum’s devastating impact. Moreover, Lero itself is a mere puppet, it’s string firmly in the grip of a powerful Central American crime syndicate known as Union Teope. Their true agenda is shrouded in secrecy but undoubtedly nefarious.

What happens at the Cosplay Convention?

In the following days, Kurumi takes refuge at Ryou’s apartment for her safety. It is revealed that Kurumi is a popular cosplayer, and she had been invited by Lero to participate at their cosplay convention. Fearing for her well-being, Kurumi convinces Ryou to accompany her to the event. As expected, the convention turns into a treacherous trap, with Kurumi coming under attack from assassins dispatched by the Union.


During the ensuing chaos, Ryou realizes that the woman who had claimed to be Kurumi’s sister is, in fact, one of the Union’s assassins, tasked with capturing Kurumi. After a brief but intense confrontation, Ryou overpowers the assassin and has her arrested. However, things take a shocking turn when a charge implanted in the assassin’s neck detonates, claiming her life. Meanwhile, Kurumi is being escorted by a high-ranking police officer, who is revealed to be a mole working for the Union within the law enforcement ranks. This treacherous officer abducts Kurumi and hands her over to Lero, allowing the organization to resume their sinister experiments on Kurumi.

What does the Union really want?

The Union Teope is an international criminal organization based in Central America. This organization has been funding research on a super drug so that they can sell this drug to military powers around the world, which would make them a lot of money. Furthermore, Lore is only a front for the Union to expand their base in Japan. Like all criminal organizations, the Union seeks power and money, and by making a superhuman serum, they intend to capitalize on war across the globe. 


How do Ryou and Kaori save Kurumi?

With the experiments on Kurumi reaching a successful conclusion, the boss of the Union Teope decides to eliminate all loose ends. In a ruthless purge, the boss orders the murder of every scientist, staff member, and even the President of Lore who was involved in the research. The Union no longer requires their services, and secrecy is a priority for them over all else. With Kurumi’s DNA proving sufficient to synthesize a stable compound free from any side effects, the boss arranges for her immediate transfer to their base in Central America. Meanwhile, Ryou’s relentless pursuit leads him to uncover Kurumi’s whereabouts at the Lore headquarters in Tokyo. Kaori, Hideyuki’s sister, convinces Ryou to let her join the mission, determined to help in any way she can.

Upon infiltrating the Lore facility, Ryou’s exceptional marksmanship is put to the test as he single-handedly eliminates the Union’s formidable forces. Kaori proves herself an invaluable ally, acting as his aide and ensuring a steady supply of ammunition, showcasing their remarkable combat compatibility. After defeating the Union’s superhuman brute, Ryou and Kaori intercept the Boss at the helipad, where he awaits a chopper to escape the country with Kurumi. In a poignant moment, the boss reveals a shocking truth: Kaori’s biological father was once a member of the Union, but upon attempting to leave the organization, he was executed by Kaori’s adopted father, Hideyuki’s father. Ridden with guilt, Hideyuki’s father made the decision to adopt Kaori, offering her a chance at a better life.


In a final standoff, the boss is overpowered, and Kaori finds herself with her gun trained on him. However, her hesitation to take a life proves costly, as the boss seizes the opportunity to retaliate. But before he can pull the trigger, a failsafe mechanism activates, and the chip implanted in his neck detonates, ending his life on the spot. Having been saved from the gruesome ordeal, Kurumi’s story meets a happy ending as she ends up becoming a successful cosplayer. As for Kaori, intending to replace her late brother’s spot as a detective, she moves into Ryou’s apartment. Even though Ryou is reluctant to have her as his detective partner, Kaori adamantly takes the role, paving the path for the canon lore from the manga. 

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Shrey Ashley Philip
Shrey Ashley Philip
A teacher, photographer, linguist, and songwriter, Shrey started out as a Biotechnology graduate, but shifted to studying Japanese. Now he talks about movies, advocates for ADHD awareness, and embraces Albert Camus.

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