A few days prior, young Detective Masayoshi Tanimura of the Tokyo Police's Community Safety division is chastised by Sugiuchi of the homicide division for misconduct while on the job. Immediately afterwards, Tanimura goes gambling while on duty and then blackmails a couple illegal businesses for hush money. He then takes his illicit gains to Homeland, a restaurant in Little Asia, where he donates them to Zhao, the restaurant's owner and leader of Asian Gateway, an organization that helps poor migrants from other Asian countries get settled in Japan and also takes care of the children of parents who've been deported.

Tanimura is tasked with arresting a low-rate Tojo Clan family. He beats them up and carries out his orders, noting that the yakuza arrest rate has skyrocketed recently. He receives a tip from one of his businesses that a witness he’s been searching for for years has finally turned up.

Tanimura speaks to an old man revealed to be a restaurant owner. Tanimura’s father was investigating the Ueno Seiwa hit when he’d been murdered, and the last thing he’d done had been to interview one of the yakuza members. The identity of that yakuza member hadn’t been known because an attempt was made on the only witness’s life, so he fled Kamurocho. He’s back because of the news about the Ueno Seiwa, and wants to get it off his chest.

The restaurant owner recognized the man Tanimura’s father spoke to as Kazuo Shibata. Tanimura thanks the man for his time and takes him into protective custody.

Tanimura goes to the Shibata Family offices near the docks and fights his way through their goons. He makes it to Shibata’s office where he finds Shibata conversing with Arai. It’s revealed that Shibata is offering Arai shelter, but clearly isn’t happy about it. He yells at Arai for his boss “forcing” him to do this, which Arai scoffs at. If Shibata wasn’t willing to do favors for him, he shouldn't have used them to secure his own spot in the Tojo.

Arai confirms that he and Katsuragi organized the incident that got Kido framed, but Arai has conflicting feelings about what it did to Kido as a result. Tanimura prepares to try to capture Arai but is foiled by the alarms going off. Tanimura reveals himself and tries to bring Arai and Shibata in.

Shibata tries to tell Tanimura something about Arai, but Arai shoots Shibata in the head before he can finish. Arai flees, and Tanimura fights through the rest of the Arai Family trying to catch up. Arai ultimately escapes, leaving Tanimura with no leads.

The Shibata Family offices are closed down as the remaining members are arrested. Tanimura is approached by Police Deputy Commissioner Seishiro Munakata accompanied by Sugiuchi. Munakata is clearly disdainful towards the Shibata Family as the two talk. Tanimura relays the information he uncovered about the Ueno Seiwa hit. Munakata tells him not to be too concerned about it, as there don’t appear to be any direct links to the current situation. Tanimura objects, saying that the hit informs the current Ueno Seiwa mindset.

Tanimura wants to find Isao Katsuragi, the high-profile man who’d notably been absent from the Ueno Seiwa hit, and talk to him. Munakata denies this, saying that the Ueno Seiwa is their wedge into the Tojo Clan. Munakata wants to bring the Tojo Clan down entirely, harboring nothing but disdain for them as an organization. Interfering with the Ueno Seiwa is interfering with their own leverage against the Tojo. Tanimura reluctantly understands.

Tanimura at first attempts to try a different angle, going to Sky Finance to try to find Akiyama. He meets Hana and interviews her. She says that Akiyama vanished recently and she’s been worried about him. Tanimura is aware of Akiyama’s connection to Arai, but is met with another dead end.

With Shibata dead, Akiyama, Saejima, Kido, and Arai all MIA, Tanimura is left extremely frustrated with no leads. He thinks back on Munakata’s order and decides to go against it.

Tanimura arrives at the Ueno Seiwa offices and is greeted by Katsuragi, who seems to be expecting him. The two talk tersely as Katsuragi asks if Tanimura is going to arrest him. Tanimura says no, and that the pressure Katsuragi is applying to the Tojo is making sure they can bring justice to as many people as they can.

Tanimura asks about the death of his father, which Katsuragi finds amusing. Tanimura suspects that Katsuragi and Shibata were in league with one another, organizing the hit to advance their own careers. Katsuragi tells him he’s on the right track, but he’s still missing one critical piece of information.

Katsuragi claims when pressed that it was not a yakuza who killed Tanimura’s father, but another cop who was his partner on the case. Tanimura refuses to believe it. Katsuragi remains vague, but makes the implication that whatever happened, the cops were involved in covering it up.

When Tanimura tries to leave, Katsuragi tries to have him killed by his men, seeming to relish in the idea of killing a cop, implying that he deliberately told Tanimura enough that he’d have to die for it.

Sugiuchi and his cops arrive, saving Tanimura and forcing Katsuragi and his thugs to flee.

Tanimura is left to wrestle with the implications of another cop being responsible for his father’s murder. He sees Sugiuchi and Munakata but brushes past them, not wanting to interact with any of his coworkers out of paranoia.

Tanimura breaks into the records room on his own and tries to find the file on his father. He ultimately does and discovers that his father’s partner on the case, and the man responsible for his death, is none other than Suguichi. Tanimura flees the police precinct, bumping into Sugiuchi on the way out, who asks if he’s okay. Tanimura brushes him off and runs, drawing Sugiuchi’s suspicion.

Tanimura heads home and tries to map out the convoluted conspiracy going on. He’s stopped by the door opening, revealing that it’s Sugiuchi. The two talk tensely as Sugiuchi tries to gauge how much Tanimura knows. Tanimura’s friends in Little Asia are nearby, ramping up the tension even more.

Ultimately, it boils over into a car chase between Tanimura and Sugiuchi. It ultimately leads to the docks, where Sugiuchi gets out and doesn’t know what to do.

Tanimura fights Sugiuchi and beats him. Sugiuchi confesses to the murder of Tanimura’s father, and confirms that the leader of the conspiracy is none other than Munakata himself. Sugiuchi at first enjoyed the perks of doing Munakata’s dirty work and acting as a cop, but Munakata ended up making him his slave. He didn’t want to kill Tanimura’s father, and apologizes for it.

The full story is as follows: Tanimura’s father investigated the Ueno Seiwa hit, speaking to Kazuo Shibata and realizing that Shibata and Katsuragi were both being used by the cops. Sugiuchi then killed him to silence him and the incident was covered up.

Tanimura tries to convince Sugiuchi that he can fight Munakata, but Sugiuchi is long since broken and full of self-loathing. Sugiuchi says that telling Tanimura this has given him peace, and wishes him luck. Sugiuchi shoots himself in the head, killing himself and leaving Tanimura once more with no leads.

Tanimura is left to deal with the knowledge that his boss is corrupt. He returns home and links the threads together to create a clear picture with Munakata at the top. He has everyone he cares about in Little Asia leave the area or else they will be targeted. He receives a call that something big’s going down and he needs to report in.

Tanimura arrives at the police precinct but something is notably wrong. The other officers look at him strangely as he moves through. Munakata arrives and speaks tersely with him for a moment before the pin drops. Munakata informs Tanimura that Sugiuchi was wired. He heard everything.

Munakata has told the officers, some of them dirty, some of them not, that Tanimura needs to be put under arrest. Munakata leaves as Tanimura is forced to fight off all his coworkers in order to escape.

Tanimura manages to beat them all, breathing heavily as he makes it outside. He’s desperate, tired, and completely alone. He’s accosted by Arai, who reveals himself to be an undercover cop working for Munakata.

Tanimura closes his eyes and prepares to accept his death before they’re interrupted by the arrival of Taiga Saejima. The mere sight of Saejima is enough to force Arai to retreat as Saejima leads Tanimura into the sewers.

Tanimura is naturally suspicious of Saejima, the killer of the Ueno Seiwa, as they head through the sewers, but Saejima says he was just another pawn trying to find out the truth.

The two of them come out at Kamurocho Hills and meet Akiyama and Majima there. Majima takes the time to reassure Tanimura, saying that he’s been gathering as many good fighters as he can who can take on the police who have enough reason to. Majima says that Munakata believes that the yakuza are something to be destroyed, but destroying the yakuza means destroying countless lives and throwing the underworld into chaos. Saejima brings up that cops and yakuza worked together to help postwar Japan, and thinks they can do it again. Tanimura ultimately agrees to help them.