Indie developer kino has released Kaitai Suiri File3: Hiura Jiken (カイタイスイリ File3：日浦事件) as the newest case in the mystery adventure series.
File3 is included in version 3.01 of Kaitai Suiri, which is available as a free Windows download. This case sends Shigure and his assistant Hina to investigate a group claiming to conduct spirit summoning, only for the investigation to uncover traces of a past Hina herself does not remember.
Quick Summary
- Japanese title: カイタイスイリ
- Romanized title: Kaitai Suiri
- Newest case: File3: 日浦事件
- Romanized case title: File3: Hiura Jiken
- Official English/global title: not announced
- Creator: kino
- Format: free indie game
- Official genre: mystery exploration adventure
- Gameplay: investigation, exploration, puzzles, and deduction
- Current version: 3.01
- File3 update date: August 10, 2026
- Confirmed platform: Windows
- Price: freeware
- Engine: RPG Maker
- Official difficulty: easy
- File1 playtime: approximately 1–2 hours
- File2 playtime: approximately 1–2 hours
- File3 playtime: approximately 1–2 hours
- Listed endings: two
- Age recommendation: all ages
- Protagonist: Shigure Shiratori
- Assistant: Hina
- File3 premise: investigation of a group claiming to summon spirits
- Central mystery: Hina’s unknown past and the unresolved Hiura Incident
- Status: available now
Announcement, Promotional Visual, and Gameplay
A Spirit-Summoning Investigation Opens File3
File3 begins when Shigure Shiratori accepts a new request and investigates a group claiming to perform spirit summoning with his assistant, Hina.
As with earlier cases, apparently supernatural phenomena are not automatically accepted at face value. Kaitai Suiri revolves around the idea that strange events have an underlying explanation that can be uncovered through investigation.
This time, however, the case quickly becomes personal.
During the investigation, Shigure and Hina discover traces of Hina’s own past—information even she did not know.
Those traces eventually lead to the unresolved Hiura Incident, turning the new File into both a paranormal investigation and an attempt to understand what happened before Hina entered Shigure’s current life.
The complete connection between the group, Hina, and the old incident is deliberately left for players to uncover.
Collected Information Can Produce New Leads
Kaitai Suiri goes beyond simply searching rooms and selecting dialogue choices.
Information obtained during interviews and exploration is stored as investigative material. Players can examine relationships between individual pieces of information and use what they have learned to infer new information.
That mechanic returns in File3.
Kino’s screenshots show evidence menus, town exploration, character conversations, and interfaces in which the player chooses what information should be applied to the current problem.
Progress therefore depends on understanding how testimony, people, earlier events, and other clues connect.
Discovering the right relationship provides another lead and moves the investigation closer to the truth.
Deduction Battles Turn Evidence into Arguments
Investigation eventually leads into the series’ deduction battles.
Rather than fighting enemies through conventional combat, players use collected information to challenge statements, expose inconsistencies, and present a more convincing explanation.
The mechanic gives clues a direct purpose beyond simply filling an inventory or database.
Support characters can also provide hints, allowing players less familiar with mystery games to continue without becoming permanently stuck.
The official Freem page lists the game’s difficulty as easy, with each File designed to take roughly one to two hours.
File1 Through File3 Form a Continuing Series
Kino recommends beginning with File1 before jumping directly into the new story.
The first case follows Shigure, a university student working under paranormal researcher Professor Setarai, as he and Hina travel to Usugishi Village to investigate the so-called curse of “Gozodobobo-sama.”
File2 brings the mystery closer to Shigure’s family when his sister Hisame reports unexplained phenomena occurring at the Shiratori residence.
Shigure investigates alongside Hina and the eccentric detective Rouan Iohara.
File3 shifts the focus to Hina herself. Because character relationships and previous developments carry across the series, playing the Files in order provides more context for the newest mystery.
Version 3.01 Is Free on Windows
Kaitai Suiri continues to be distributed as freeware.
Version 3.01 is available through Freem as a roughly 303 MB download, with Windows 8, Windows 10, and Windows 11 listed among its supported environments.
The game was created using RPG Maker and carries an all-ages recommendation on the distribution page.
Kino also permits gameplay videos and livestreams under the published guidelines, including a request to place the game title and a link to its page or the creator’s site in the description.
File3 is part of the latest Kaitai Suiri package rather than a separately sold game.
Why This Matters
1) The third case becomes personal
The central investigation now reaches into Hina’s own history rather than remaining an unrelated assignment.
2) Information is an active gameplay resource
Collected clues are connected to create new deductions and are later used directly in deduction battles.
3) Horror is only one part of the experience
Spirit summoning and strange phenomena provide the atmosphere, but the game ultimately asks players to investigate the cause behind them.
4) All three cases remain free
The current release includes three Files, each designed as a relatively short mystery that can be completed in about one to two hours.
Game Information
The important details currently known are:
- Kaitai Suiri is a mystery exploration adventure by kino
- its original Freem registration dates back to September 2022
- File3: Hiura Jiken is included in version 3.01
- the game page was updated on August 10, 2026
- File3 follows Shigure and Hina investigating a spirit-summoning group
- the investigation uncovers information about Hina’s past
- those clues lead toward the unresolved Hiura Incident
- players collect information through interviews and exploration
- existing information can be used to infer new leads
- deduction battles are a central mechanic
- support characters can provide hints
- every File takes approximately one to two hours
- the current listing specifies two endings
- the game is free on Windows
- it carries an all-ages recommendation
- RPG Maker was used for development
- streaming and gameplay videos are permitted under kino’s guidelines
- the game is available through the official Kaitai Suiri Freem page
- development updates are posted through kino’s official X account
Closing
Kaitai Suiri File3: Hiura Jiken expands kino’s mystery series with a case tied directly to Hina’s unknown history.
Version 3.01 has been available as a free Windows release since August 10, 2026. New players are encouraged to begin with File1 to follow the character relationships and continuing developments in order.
- kino Official X — File3: Hiura Jiken Release Announcement, Gameplay Screenshots, and Investigation System
- Freem — Official Game Page, File1–3 Story, Version 3.01, Playtime, Platform, and Download
- PLiCy — Kaitai Suiri Game Page and Original Series Information
- Newcomer Free Game Contest — File1 Premise, Core Deduction System, and Creator Information
