Detective Conan Announces First Viewer-Participation Mystery as 30th Anniversary Special Gets September Date

Detective Conan has revealed new details for its 30th-anniversary celebrations, including a two-hour television special airing September 25 in Japan and a separate original anime designed to let viewers try to identify the culprit themselves.

They are not the same project. Several reports have bundled the two announcements together, and it’s easy to see why — both were unveiled on the same day, both are billed as anniversary projects, and both are murder mysteries. But they have different titles, different staff, different formats, and only one of them has an air date.

Two Projects, Not One

Project	Format	Date
30-gō Satsujin Jiken (“The 30th Murder Case”)	Two-hour TV special	September 25, 2026, in Japan
Misohitojima no Satsujin (“The Misohitojima Murder”)	Viewer-participation original anime	TBA

The 30th Murder Case: What’s Confirmed

Detective Conan: 30-gō Satsujin Jiken airs September 25 at 9 p.m. JST on Nippon TV and Yomiuri TV’s Friday Roadshow block, in a two-hour slot. It’s a fully original story, not adapted from the manga, and it’s the franchise’s first new two-hour special in roughly a decade.

The premise centers on a newly issued ¥10,000 note. Counterfeit bills tied to that new currency turn up at a murder scene, and the case escalates from there: Conan and the Detective Boys visit the National Printing Bureau’s Nagano facility as investigators dig into the forgery operation, while Conan and Heiji Hattori head to Osaka, which the story points to as the source of the counterfeit bills. The broadcaster describes the case growing into a national-level crisis rather than a self-contained local murder.

Fumiharu Kamanaka directs, with a script by Takeharu Sakurai — both established names on the franchise’s theatrical films. TMS Entertainment animates, as it does the rest of the series. NTV and Yomiuri TV are billing the cast as one of the largest in the show’s history, with actress Elaiza Ikeda joining as a guest voice for the special: she plays Toko Satomi, a document examiner at the National Police Agency’s forensic science institute, brought in to determine whether the recovered bills are genuine.

The Franchise’s First Viewer-Participation Anime

The second project is where the real novelty is. Misohitojima no Satsujin — written with the kanji for “31 Island” but read as “Misohitojima” — is a separate original anime built around a different idea entirely: rather than revealing the killer at the end the way every other Conan story does, this one is structured so the audience is meant to work out the culprit for themselves before the answer is given.

That’s a genuine first for the anime. Reports describe it as an audience-participation format the series has never attempted before, and the concept has been in the works for a long time — director Yasuichirō Yamamoto has said he first came up with the idea more than twenty years ago, after watching an armchair-detective drama, and held onto it until this year’s anniversary lineup gave him an opening to pitch it. Takahiro Ōkura, a mystery novelist who has also written for Lupin the Third Part 6, handles the script.

It’s worth being precise about what “viewer participation” actually means here. Nothing about this project has been described as branching storylines, clickable choices, multiple endings, or anything resembling interactive streaming formats like Netflix’s Bandersnatch. The concept, as staff have described it, is closer to an armchair-detective challenge: viewers watch the case unfold and are invited to name who they think did it, with the real solution still fixed and revealed by the show itself. No specific participation mechanism — whether that’s a companion app, a social media prompt, or something built into the broadcast — has been confirmed yet.

No air date has been set. Reports indicate it’s expected to close out the anniversary year in the show’s regular weekly broadcast slot, after the other commemorative specials have aired, but Nippon TV and Yomiuri TV haven’t confirmed a date.

What International Viewers Should Know

Both announcements are for Japanese broadcast only. Neither Nippon TV, Yomiuri TV, nor the official Detective Conan production committee has announced a Crunchyroll release, a Netflix release, an English dub, or any other international distribution plan for 30-gō Satsujin Jiken or Misohitojima no Satsujin. If you’re outside Japan, there’s currently no confirmed way to watch either one when it airs.

Separately, Netflix Japan has put together a domestic 30th-anniversary tie-in of its own: a set of 30 curated episode collections organized around individual characters like Conan, Ran, Shinichi and Kaito Kid. That’s a library curation project for the existing series, not a new special, and it’s a Japan-only offering rather than an international rollout.

Why 2026 Is the 30th Anniversary

Detective Conan’s TV anime began airing in January 1996, making 2026 the show’s 30th year on air — one of the longest continuous runs of any anime still in weekly production. Both new projects are part of a broader slate of anniversary programming NTV and Yomiuri TV have been rolling out through the year, but the September 25 special and the still-dateless viewer-participation anime are the two pieces with genuinely new stories attached, which is why they’re the ones worth tracking closely.