The AD-9 conspiracy was a major political, criminal, and medical conspiracy in Japan that occurred from 2015 to 2019, with the developmental drug AD-9 at the center of it. Efforts by both the Advanced Drug Development Center and the Ministry of Health, Labour and Welfare to cover up the promising drug's failures and lead researcher Yoji Shono's kidnapping, involuntary testing, and murder of Kyorei-kai yakuza resulted in a political scandal that resulted in the arrest of Vice-Minister of Health Kaoru Ichinose and several other corrupt officials, the closure of the ADDC, the cancellation of AD-9's development. As the yakuza were drawn into the conspiracy through both the Kyorei-kai and Matsugane-gumi's involvement with the ADDC, major shakeups occurred within these small families as the Kyorei-kai's plans to expand into Tokyo were quashed and the Matsugane-gumi dissolved not long after the murder of its patriarch Mitsugu Matsugane.
Background[]
The faction at the center of the AD-9 conspiracy was the Advanced Drug Development Center, a Tokyo-based medical facility part of the Health Ministry's Medical Institute. The ADDC was founded in 2002 by politician Kaoru Ichinose with the purpose of providing cozy retirement jobs for former politicians. As Japan solved its aging crisis, however, the ADDC's work became less important, and it was faced with closure after the Great Recession. The Kyoto-based businessman Shigeru Kajihira, who was also the main financial backer of the Kyorei-kai yakuza syndicate, hoped to buy the desirable plot of land atop which the failing ADDC sat, and Health Minister Naohisa Kazami authorized the land's sale for 100 billion yen. In 2015, Kajihira employed the help of ADDC vice-director Toru Hashiki to sabotage the center by fueling projects being developed there, only to sell the projects to rival companies.
At the same time, however, ADDC researcher Yoji Shono accelerated his research on a new drug that could cure Alzheimer's and dementia, codenamed AD-9. The animal trials on mice were successful, leading Shono to begin his own secret clinical trial by testing it on the Alzheimer's patient Koichi Waku. When Waku died, Shono framed the janitor Shinpei Okubo for the killing, and, as Okubo already had a criminal record, he was quickly charged with Waku's murder. With the help of lawyer Takayuki Yagami, however, Okubo was able to prove his innocence. Fearing that he would be subjected to increased scrutiny, Shono headed to Okubo's apartment, injected his sleeping body with alcohol, stabbed his girlfriend Emi Terasawa fifteen times, and set the apartment on fire, making it look like the murderous Okubo had drunkenly killed his girlfriend on being released from jail. This incident destroyed Yagami's legal career, forcing him to leave the Genda Law Office and open the Yagami Detective Agency in Kabukicho. In 2017, Shono authored a research paper on AD-9, which ADDC director Ryusuke Kido passed off as his own in order to give it a higher profile. At a presentation on AD-9, Kido was able to drum up enthusiastic support for the drug, reversing the ADDC's decline and thwarting Kajihira and Hashiki's sabotage. Shono later privately revealed AD-9's failures to Kido, as well as his murder of Waku, but he persuaded Kido to cover this up until he could make AD-9 work, as it could be a revolutionary drug. Kido agreed, and they soon secured the help of Vice-Minister of Health Ichinose with protecting the AD-9 project.
History[]
With AD-9 officially announced, Shono - with Ichinose's backing - continued human experimentation of the drug on subjects in a secret lab established in the derelict Monsieur Lee love hotel in Kabukicho. Through Ichinose's middleman Mitsuru Ishimatsu, Shono contacted Matsugane-gumi captain Kyohei Hamura, who was known to take on hit contracts to restore his family's flagging fortunes, and who relied on the corrupt policeman Mitsuru Kuroiwa to carry them out. When Ishimatsu asked Hamura to kidnap test subjects for AD-9, an initially disgusted Hamura decided that the Kyorei-kai would be worthy targets, as their lieutenant Akira Murase had been sent to Tokyo to establish a foothold for the clan ahead of the ADDC's demolition and redevelopment, and the Health Ministry also had an axe to grind with Kajihira's clan. The first of these victims was Kenkichi Mashiba, who was kidnapped in August 2018, taken to Monsieur Lee, and given AD-9. He immediately died, with the toxins from the drug giving his eyes a blue pigmentation. To cover up the proof of AD-9's failure, Shono had Kuroiwa gouge out Mashiba's eyes to make his death look like a brutal gangland killing. When Yasuo Kunimura was kidnapped in October and Toshiro Kume in December, they both died from the AD-9 and also had their eyes gouged out, causing Kuroiwa to be nicknamed "the Mole."
The December 2018 murder of Kume was a turning point in the conspiracy, as Kume and his boss Murase had been spotted fighting with Matsugane-gumi captain Hamura outside Club Amour a few hours before Kume's death. Hamura was charged with Kume's murder, causing him to request that private detective Takayuki Yagami, a friend of his boss Mitsugu Matsugane, help prove his innocence. Matsugane, together with the lawyer Masamichi Shintani of the Genda Law Office and fellow private detective Masaharu Kaito (himself a former Matsugane yakuza), were able to establish that Hamura had been at Sauna Goten at the time of the murder, and they also crossed paths with the Kyorei-kai on several occasions while attempting to persuade Murase to testify at the trial. Murase, like the rest of the Kyorei-kai, believed Hamura to be responsible, causing them to attempt to sabotage Hamura's defense. However, the defense managed to secure the help of a host whom Hamura had assaulted in an alleyway at the same time as Kume's murder, and this witness' testimony persuaded the judge to find Hamura not guilty of murder.
Yagami was left unsatisfied, as he believed that Hamura was still involved with the murder, having taken Kume inside Club Amour before leaving as Kume disappeared. Yagami coined the nickname "the Mole" to refer to the eye-gouging associate of Hamura's, and, while Hamura warned him not to investigate any further, Yagami enlisted the help of the Genda Law Office in trying to find the real murderer. Shintani, who was jealous of Yagami's successes, started his own investigation, and, using information gleaned from Hamura during the trial, he decided to contact Shono and find out how he and the ADDC were involved in the murders. When Ichinose discovered that Shintani was onto Shono, he personally gave the order for Hamura to kill him, and he demanded that he do so without payment as recompense for his failure. Hamura knocked out Yagami's police acquaintance Kazuya Ayabe shortly after Ayabe met with Yagami at Bar Tender, stole his gun, shot Shintani, dumped Shintani's body in the closet of the Yagami Detective Agency, and returned the gun to Ayabe before he awoke. Ayabe was thus framed as the murderer and was soon sent to jail, pending trial; the rifling on the bullet only matched his gun.
Meanwhile, Yagami and Kaito were lured into meeting with Kajihira, who kidnapped Kaito's old girlfriend, the prosecutor Mafuyu Fujii, to lure him to the Honmaruen cabaret. There, Kyorei-kai captain Satoshi Shioya had set up a base in preparation for war with the Matsugane. Kajihira hired Yagami to find out the Mole's true identity, as he wanted to ensure that the ADDC could still close down, while stopping the attacks on his men. Yagami and his associates - who included Kaito, Emi Terasawa's brother Fumiya Sugiura, Matsugane-gumi lieutenant Toru Higashi, and Genda Law Office lawyers Saori Shirosaki and Issei Hoshino - proceeded to look into the ADDC's affairs, making multiple visits to the building to confront Shono and Kido. Yagami's continued investigation made him a target of Hamura, who ordered the Matsugane-gumi to initiate a manhunt for Yagami and murder him when found.
As the ADDC was uncooperative with the investigation, Yagami and Kaito resorted to tracking down Hamura. While they failed to capture him at a cho-han parlor in the Golden Gai and narrowly escaped dying in a fire set by Hamura's men, they decided to lure him out by having Yagami visit several Matsugane-owned businesses and picking fights. Yagami and Kaito eventually fell into Hamura's own trap, as they were lured into a vacant lot in Little Asia and ambushed by Hamura. Kaito was shot after rebuking Hamura for betraying their boss Matsugane, but Sugiura arrived in time to rescue Yagami from being shot as well. Using wiretaps that Yagami had set up at the Matsugane HQ, Sugiura tracked Hamura and Kaito down to the Soleil Building, where Yagami and Sugiura fought off the Matsugane-gumi, defeated Hamura, and rescued Kaito. Patriarch Matsugane, who had been rendered powerless by Hamura's takeover of the family years earlier, threw in his lot with his adoptive sons Kaito and Yagami. With the Kyorei-kai as allies, Yagami and the others decided to move Hamura to the Kyorei's Honmaruen base for interrogation. There, he divulged many details about the Mole, apart from his name.
The interrogation was interrupted when Hamura's men tracked him down to Honmaruen and set the building on fire. They were able to capture Murase and send him back inside while wearing a suicide vest, hoping to kill Shioya. However, they detonated his bomb too early, only killing him. The Matsugane men then stormed the building, forcing Yagami to fight them off as he evacuated Matsugane and Hamura. Kuroiwa arrived soon after, intent on killing Hamura to conceal his identity. Matsugane threw himself in front of Kuroiwa's bullets, giving his life to save his right-hand man, and Kuroiwa was forced to flee as the flames intensified. Hamura then revealed Kuroiwa's name to Yagami before going into hiding, leaving the Matsugane-gumi in chaos, with Kengo Kajikawa attempting to assume control over its bellicose rank-and-file.
Kuroiwa took Yagami into questioning after the fire, and it was there that Yagami revealed that he knew all about Kuroiwa's actions, causing Kuroiwa to promise to kill him at an opportune time. On his release, Yagami learned that Shioya had been killed by the Mole as well. Not long after, Kajihira warned Yagami that Okubo was soon to be executed, forcing Yagami to speed up his plans to prove his and Ayabe's innocence. With the help of Shirosaki, who posed as a journalist and seduced Kido, Yagami was able to catch Kido on film sexually harassing Shirosaki. He then had Shirosaki lure Kido to the Yoshida Batting Center in Kabukicho, where he and his associates interrogated him and discovered the existence of Shono's secret lab in Kabukicho. Yagami had Kido call Ishimatsu and tell him that Yagami was onto the secret lab, and Yagami followed Ishimatsu from the Health Ministry's Millennium Tower offices to Monsieur Lee, where he fought his way through several Ministry of Health-employed homeless hitmen and discovered Shono at his lab. He arranged for the police and prosecutor Kunihiko Morita to arrive, informing them that a search of the place would reveal the truth about AD-9, but Ichinose arrived shortly after and told the police that the lab was a classified Health Ministry facility. Morita, who had secretly helped the ADDC cover up the murders in exchange for ensuring that AD-9 could succeed (having lost his own mother to Alzheimer's), agreed to call off the search, causing Yagami to realize his betrayal. At the same time, Kuroiwa rescued Kido from Kaito and Higashi, leaving Yagami with no more leads.
Just then, Hamura emerged from hiding, dressed as the Mole, to lure Yagami and Kaito into a meeting on a nearby rooftop. There, he handed over a secret recording of a phone call between himself and Ichinose revealing Ichinose's role in directly ordering Shintani's death. With this evidence in hand, Yagami set about preparing to expose Ichinose's corruption and the AD-9 conspiracy at Ayabe's trial a month later. He persuaded Kido to testify about AD-9's failure, having him claim to have only recently discovered the failure from Shono so that he could be exculpated from the murders. Finally, Sugiura supplied Hattori with photos he had taken of the secret lab, enabling Hattori to publish an article on the morning of the trial that would reveal Shono and Ichinose's corruption to the world.
In January 2019, at Ayabe's trial, Kido testified to AD-9's lethality, and Hamura gave a damning testimony revealing Ichinose's role in Shintani's murder. Desperate, Ichinose had Ishimatsu send a hit squad to kill Kuroiwa before he could be arrested. Kuroiwa survived the hit attempt at Theater Square, killing his attackers before deciding to seek vengeance against Shono. Yagami and Kaito learned from one of the injured hitmen that Kuroiwa was on his way to the ADDC, where Yagami, Kaito, Sugiura, and Higashi fought off several of Kuroiwa's fellow policemen before Yagami and Sugiura gave chase to the murderer. A desperate Kuroiwa, sure of his own doom, shot several policemen and security guards as he made his way towards Shono's office. While he briefly derailed the chase by blowing up the bridge between the medical and research wings, Yagami and Sugiura used the loading dock entrance to enter the research building. While Sugiura kept Shono out of harm's way, Yagami was able to defeat Kuroiwa in an intense battle. Police arrived to arrest Kuroiwa shortly after, but they shot and mortally wounded Kuroiwa when he charged at Shono. Shono, insulted at Kuroiwa's joking about the failure of his project, injected himself with the newest batch of AD-9 to prove its efficacy. However, he suffered the same symptoms as his earlier victims and died, with Sugiura recording the entire incident on his phone. Yagami and Sugiura then returned to the trial, where they were able to use the video to unmask AD-9's failure and Shono's role in the conspiracy, including his murder of Emi Terasawa.
Aftermath[]
As a result of these developments, Ayabe was found not guilty of murder, Okubo was immediately released from prison, Ichinose was arrested for soliciting murder, Morita was arrested for official misconduct, and Ichinose's policies fell under legal review, resulting in his ties to Kajihira being exposed. While the ADDC was indeed closed due to the AD-9 scandal, the Kyorei-kai was not sold the land for redevelopment, meaning that they had sunk billions of yen into the acquisition project for nothing.
The Matsugane-gumi, already ravaged by the conflict, dissolved amid the "Great Dissolution" later that year. Likewise, the Kyorei-kai retreated back to Kansai. Ichinose was replaced as Vice Minister by the more popular politician Reiko Kusumoto, who would herself be implicated in a corruption scandal in 2021 after having the teacher Yu Kitakata murder Shinya Kawai, who had bullied her son Mitsuru Kusumoto into a suicide attempt that left him in a coma.