Spirit Circle Anime: December 2026 Release, Cast & 18 Episodes

Last checked: November 7, 2026, against the official Spirit Circle site, Twin Engine's PR TIMES release, Anime News Network, and Crunchyroll News.

This is the first screen adaptation of Satoshi Mizukami's completed reincarnation fantasy, and it lands as the late director Tatsuo Satō's final series. If you track Winter 2026–27 releases, this belongs next to the titles already on our 2026 anime release schedule and the live anime release calendar. For where to watch once a platform is named, keep where to watch bookmarked.

What we know

The official ON AIR line is blunt: broadcast and streaming begin from December 2026. Twin Engine's press release and assistant director Kentaro Mizuno's comment both state the full 18-episode run, which is longer than a standard single cour and shorter than two full cours — a fit Mizukami himself called out in his author comment.

What is unconfirmed

Treat anything outside the table above as not confirmed:

• Exact premiere day and Japanese TV network/slot
• Which services will carry the global stream (Crunchyroll News: "Streaming platforms will be confirmed at a later date")
• Dub language plans, simulcast clock, or region blackouts
• Blu-ray / streaming exclusive extras
• Whether every past-life arc from the six volumes is adapted 1:1

REMOW's English framing ("air in Japan and also stream globally") is a distribution intent, not a named license. Do not assume Crunchyroll, Netflix, HIDIVE, or anyone else until the committee posts it.

Cast and staff

Main cast

Key staff

Satō died in April 2026. Twin Engine, NAGOMI, and EOTA's joint statement says the team finished the series carrying his intent forward, and they frame this as his final directorial work. That is not marketing filler: the same PR package is where the 18-episode count and December window were locked for English reporters.

Story setup (spoiler-light)

Fuuta Okeya is a middle-schooler who can see spirits. A mysterious transfer student, Kouko Ishigami, arrives and claims a reincarnation grudge: she intends to destroy his soul and break the cycle. Fuuta uses the Spirit Circle to relive past lives across eras — ancient settings through a far future — to learn why they keep colliding.

Seven Seas' English synopsis (quoted via Crunchyroll News) stresses the birthmark Kouko recognizes as a curse she left on him in a previous life. The teaser PV lines that Twin Engine published lean on Kouko's threat that Fuuta will "die seven more times," which matches Mizukami's comment that the story walks seven lives. That is the structural pitch: not a weekly monster-of-the-week shonen, but a closed reincarnation mystery with a finished manga.

If you have never read Mizukami, the closest comparison points on this site's shelf are other dense, complete fantasies rather than endless battle series. His The Lucifer and Biscuit Hammer already got a 2022 anime; Sengoku Youko got a three-cour run in 2024 (ANN). Spirit Circle sits between those: shorter manga, heavier thematic payoff.

Why December 2026 matters for trackers

December sits at the edge of Fall 2026 and the start of Winter 2027 planning. An 18-episode show that starts in December will almost certainly spill into early 2027, so calendar tools that only tag "Fall" or "Winter" will mis-bin it until a day-one air date lands.

Practical checklist for December:

1. Watch the official site and @spiritcircle_pr for the network slot and streamer drop.
2. Add the title to your personal Winter watch list once the day is posted — our release calendar is the hub for dated entries.
3. If you want the manga first, the English run is complete via Seven Seas; you are not waiting on an ongoing localization.

Music

Anna Nagase (Kouko) sings the ending 「此処がどんな世界でも」 / Koko ga Donna Sekai Demo, rendered in English coverage as "No Matter the World." Twin Engine says the song was written for the series. Credits on the PR TIMES page: lyrics by UiNA, music and arrangement by Tatsuya Katō. Nagase's comment frames it as her first solo singing release. Opening theme details were not in the November 5 package.

How this compares to other Mizukami adaptations

An 18-episode count on a six-volume manga is unusually generous on a per-volume basis. That is the information gain here: the committee is signaling coverage breadth, not a teaser cours that stops mid-mystery.

Reading order if you start now

You do not need the manga to follow the anime's pitch, but because the manga is finished, binge readers have a clean choice the incomplete-shonen crowd never gets:

1. Anime-first: wait for December, then decide whether the 18-episode adaptation scratched the itch.
2. Manga-first: read all six English volumes (Seven Seas), then watch for how Satō / Mizuno paced the seven lives into 18 episodes.
3. Hybrid: read through the early school / first past-life stretch, then switch to weekly episodes once the streamer is named.

There is no filler list problem here — the source is a closed six-volume story. The risk is adaptation compression, not filler padding, which is why the 18-episode commitment is the number to remember from the November 5 announcement.

Production notes worth tracking

• Final Satō series: Martian Successor Nadesico, Stellvia, and Atom: The Beginning fans will watch this for directing fingerprints even if reincarnation fantasy is not their usual lane.
• NAGOMI × EOTA: Twin Engine group studios sharing the load; English coverage consistently lists both.
• Teaser PV: hosted via the YouTube URL Twin Engine published in the PR TIMES package (https://youtu.be/RQnO-Uj4HD8); useful for tone, not for episode titles.
• Official X: @spiritcircle_pr for slot and streamer drops after this article's check date.

None of those notes change the release window. They are the production context that separates this announcement from a vague "anime project in the works" teaser.

FAQ

When does the Spirit Circle anime release?

December 2026 in Japan for broadcast and streaming. No exact calendar day has been posted as of November 7, 2026.

How many episodes is Spirit Circle?

18 episodes, confirmed in Twin Engine's press materials and Kentaro Mizuno's staff comment.

Where can I watch Spirit Circle?

Not announced yet. Coverage says it will stream globally; Crunchyroll News explicitly says platforms will be confirmed later. Check back against the official site and our where to watch page once a service is named.

Who directed Spirit Circle?

Tatsuo Satō, with series composition; production was completed under assistant director Kentaro Mizuno after Satō's death in April 2026. Animation is by NAGOMI × EOTA, produced by Twin Engine.

Is the Spirit Circle manga finished?

Yes. Serialization ran from 2012 to 2016 in Young King Ours; six volumes. English readers can finish it through Seven Seas (physical) and the earlier Crunchyroll Manga simulpub.

Is there an ending theme yet?

Yes. Anna Nagase performs Koko ga Donna Sekai Demo ("No Matter the World"), written for the show. Opening theme: not in the November 5 announcement.

Sources

• Official Spirit Circle site — ON AIR, CAST, STAFF, MUSIC
• Twin Engine PR TIMES release (2026-11-05) — 18 episodes, staff comments, ED credits
• Anime News Network (2026-11-05) — REMOW English announcement, cast, Satō final work
• Crunchyroll News (2026-11-05) — global December window; platforms TBA

PrimeTime Anime news desk · November 7, 2026. We will refresh this page when a premiere day or streamer is posted.