AIBOU Is Going Back to 2009—Why Bring Back Takeru Kanbe?

Kaoru Kameyama is handing things over to Takeru Kanbe. Again.

On October 13, 2026, TV Asahi announced an extraordinary change for AIBOU: Tokyo Detective Duo Season 25. Kaoru Kameyama, played by Yasufumi Terawaki, will give way to Takeru Kanbe, played by Mitsuhiro Oikawa, at some point during the season beginning October 21.

For longtime viewers, that pairing should sound suspiciously familiar. Kameyama left the series in 2008. Kanbe arrived in 2009. Now, 17 years later, the same succession is happening all over again.

After 26 years on television, AIBOU is repeating an old partner change. And rather than introduce a new actor, it is bringing back a detective who left the Special Task Unit 14 years ago.

Is this simply nostalgia? Or can a detective series with a quarter-century of history do something more interesting with its former characters?

I went back through the broadcast dates and character histories. The answer is more complicated than a straightforward reunion.

Six Partners, but Only Four Actors

For readers unfamiliar with the series, AIBOU began in 2000 as a Japanese television detective drama centered on Ukyo Sugishita (Yutaka Mizutani), an exceptionally perceptive investigator assigned to the Special Task Unit, known in Japanese as Tokumei-gakari.

The unit belongs to Tokyo’s Metropolitan Police Department, but it is an obscure, sidelined section where unwanted officers tend to end up. Sugishita’s unusual methods make him a difficult colleague, and the identity of his partner has become one of the show’s defining features.

Across its first 26 years, four actors have played his principal partners: Yasufumi Terawaki, Mitsuhiro Oikawa, Hiroki Narimiya and Takashi Sorimachi. But by Season 25, the series will have had six numbered partner tenures.

Period	Character (Actor)	Partner Tenure
2000–2008	Kaoru Kameyama (Yasufumi Terawaki)	First
2009–2012	Takeru Kanbe (Mitsuhiro Oikawa)	Second
2012–2015	Toru Kai (Hiroki Narimiya)	Third
2015–2022	Wataru Kaburagi (Takashi Sorimachi)	Fourth
2022–2026	Kaoru Kameyama (Yasufumi Terawaki)	Fifth
From 2026 (announced)	Takeru Kanbe (Mitsuhiro Oikawa)	Sixth

Note: There was no regular partner between Kameyama’s departure in December 2008 and Kanbe’s debut in March 2009. The exact timing of the Season 25 handover had not been announced as of October 16, 2026.

That gives us an odd little piece of television arithmetic: six partner tenures, but only four actors. The first two detectives have each returned for a second stint.

It also raises an obvious question. Why does this long-running series keep finding new uses for its old partners?

The Original Handover Included a 91-Day Gap

Let’s revisit 2008.

Kameyama’s departure came in Season 7, Episode 9, broadcast on December 17, 2008. The episode, titled “Level 4 — Part Two: Kaoru’s Final Case” in translation, ended with Kameyama deciding to leave Japan with his wife Miwako.

He was going to Salwin, a fictional country in South Asia, to carry on the work of a deceased friend and help its children.

Kanbe, however, did not appear in the following episode. His debut came in the Season 7 finale, “Tokumei,” broadcast on March 18, 2009.

Subtracting the two broadcast dates gives us 91 days between Kameyama’s departure and Kanbe’s debut. This measures real-world broadcast dates, not the amount of time that passed within the fictional story.

More revealing is the episode count. Episodes 10 through 18 amount to nine episodes without a regular partner assigned to Sugishita.

During those stories, Sugishita investigated alone or worked with different supporting characters. For a series built around the chemistry between two detectives, this was an unusual experiment.

AI-generated illustration imagining the Special Task Unit during the nine-episode period without a regular partner. It is not an actual scene or still from AIBOU.

The 2026 announcement suggests a different situation. TV Asahi has confirmed that Kameyama will hand over to Kanbe during Season 25 itself. But it has not said whether there will be another gap, whether both detectives will work on a case together, or exactly how the transition will happen.

The names may be the same. The mechanics of the handover are not necessarily the same at all.

Kanbe Originally Arrived to Spy on Sugishita

There is another important detail that makes the 2009 comparison worth examining.

When Takeru Kanbe first entered the Special Task Unit, he wasn’t there because he admired Sugishita or wanted to become his partner.

Kanbe was a career officer from Japan’s National Police Agency, the national-level organization responsible for coordinating and supervising police administration. He had been sent to the Tokyo unit under orders from senior officials.

His secret assignment was to assess whether the Special Task Unit was useful to the police organization at all. In other words, he was there to monitor Sugishita.

Imagine meeting your new partner and discovering that his real job is to evaluate whether your department deserves to exist. Not exactly the beginning of a warm friendship.

Yet the arrangement changed over time.

By the Season 8 finale, Kanbe had rejected an opportunity to return to the National Police Agency and chosen to stay with Sugishita. He increasingly followed his own sense of justice rather than simply obeying the organization that had sent him.

Then came the Season 10 finale, “Crime and Punishment,” in 2012. A murder investigation involving human cloning brought Kanbe and Sugishita into serious conflict over their principles.

Kanbe felt responsible for pressuring Sugishita to compromise his convictions and considered leaving. Although Sugishita was prepared to keep him, an intervention from above ultimately sent Kanbe back to the National Police Agency.

He was never just an admiring subordinate. Kanbe was a man intelligent and stubborn enough to challenge Sugishita’s idea of justice—and make him uncomfortable in the process.

Kameyama and Kanbe Reveal Different Sides of Sugishita

Kaoru Kameyama is the more instinctive partner. He connects with victims, follows his emotions and is willing to act before every detail has been neatly arranged. Sugishita supplies the cool-headed analysis; Kameyama supplies the human urgency.

Kanbe brings a different kind of friction.

Like Sugishita, he is quick-thinking, analytical and proud of his abilities. Their disagreements are not always about emotion versus logic. Sometimes they are two intelligent men arriving at competing ideas of what justice requires.

This distinction resurfaced in Season 21, Episode 20, “13 — Ransom for the Dead,” broadcast on March 8, 2023.

The episode brought Kameyama and Kanbe face to face for the first time. Kanbe also recalled something Sugishita had told him back when they worked together: he could not simply take Kameyama’s place.

That line is more revealing than it initially sounds.

For Sugishita, a partner was not an interchangeable employee who could be swapped for the next available candidate. Kameyama and Kanbe occupied different places in his life, and their differences mattered.

AI-generated illustration imagining Sugishita with his two former partners, Kameyama and Kanbe. It represents their different personalities and does not depict an actual scene from the series.

The Two Former Partners Had Already Met in 2023

Kanbe’s return in 2026 might seem sudden if you assume that his departure in 2012 meant he had disappeared from the series permanently.

But he remained part of the fictional police organization, and the writers occasionally brought him back.

In the January 1, 2019 special “Diva,” from Season 17, Sugishita called on Kanbe for help when his then-partner, Wataru Kaburagi, was in danger.

Then, on March 8, 2023, Kanbe appeared in the first half of Season 21’s two-part finale and finally met Kameyama. He joined the investigation from his position at the National Police Agency and returned in the second half the following week.

That means the first and second partners had already worked on the same case roughly three and a half years before the 2026 handover announcement.

Was their 2023 meeting intended as an early setup for Kanbe’s return in Season 25?

There is no public evidence establishing that. It would be a stretch to declare it a carefully planted three-year clue.

What we can say is simpler—and more useful. The series had already demonstrated that Kanbe could reenter Sugishita’s professional life without requiring a complete reset of his character.

So Why Bring Back Kanbe Instead of Casting Someone New?

In its October 13, 2026 announcement, TV Asahi presented the handover as something made possible by the show’s unusually long history. Yutaka Mizutani emphasized that this was the sort of development only AIBOU could pull off.

But the announcement did not give a specific production reason for choosing Kanbe over an entirely new actor.

That distinction matters. What follows is an editorial interpretation, not a claim about the producers’ private intentions.

In 2009, Kanbe arrived as an outsider tasked with judging the Special Task Unit. Sugishita hardly knew him. Their story was about whether the suspicious newcomer could become a genuine partner.

In 2026, Kanbe is no newcomer. He knows Sugishita’s habits, his intelligence, his pride and the risks of his uncompromising approach to justice.

He has also returned to the National Police Agency and maintained connections inside the police hierarchy. That gives the writers a set of personal and institutional relationships that a newly introduced detective would not possess.

A new partner would require the series to build another relationship from the beginning. An old partner allows it to begin with shared memories, unresolved tensions and a history the audience may remember better than either man would like.

In 2009, the question was: “Can this man become Sugishita’s partner?” In 2026, it is: “Why is a man who has already been his partner coming back?”

Same characters. Same desk, perhaps. But a completely different dramatic question.

The precise reason for Kanbe’s return, and the circumstances of Kameyama’s next departure, were still undisclosed as of October 16, 2026.

Editor’s Note

My first reaction to the announcement was pretty much, “Wait, Kanbe again? Seriously?” After all these years, couldn’t the producers find a new detective?

But looking back at the old episode dates changed my mind a little.

Kameyama left, and Sugishita spent nine episodes without a regular partner. Then the replacement finally turned up—and he was effectively a spy sent to keep an eye on the whole operation.

Seventeen years later, that same man is being sent back. Only now, he knows exactly what kind of trouble he is walking into.

What interests me most isn’t simply that Kanbe is returning. It’s how Sugishita will react.

Will he welcome Kanbe back to the Special Task Unit with the same carefully measured politeness he once showed him? Or will two men who know each other this well dispense with the ceremony altogether?

In most long-running shows, bringing back the early cast would make me suspicious of creative exhaustion. And yes, there’s still a whiff of recycling here.

But AIBOU has accumulated something unusual: decades of shared cases, arguments, departures and unfinished personal history.

Sometimes reusing an old character is lazy. Sometimes the accumulated baggage is exactly what makes a new story possible.

That’s the part I want to see.

References