Japanese publisher Shueisha Games has released a playable demo of Seasons of Books and Keys, an upcoming mystery adventure based on the novel by award-winning author Honobu Yonezawa. Developed by iMel Inc., the game combines interactive storytelling, character-driven drama, and puzzle-solving, allowing players to investigate mysteries directly rather than simply follow a predetermined narrative.
The demo is available on Steam alongside Steam Next Fest, which began October 19, 2026, at 10 a.m. Pacific Daylight Time. It includes the complete opening chapter, offering PC players an introduction to the game’s characters, narrative structure, and investigative mechanics.
Seasons of Books and Keys Demo Includes Complete Chapter 1
The playable demo features the entire first chapter, titled “913,” introducing a mystery involving two students and a seemingly impossible task.
The story follows Jiro Horikawa and Shimon Matsukura, who are spending an ordinary afternoon in their school’s library when an older student, Mari Urakami, approaches them with an unusual request.
Urakami wants the pair to open a locked safe left behind by her late grandfather. Despite previous attempts, nobody has managed to unlock it.
Their only clue is a statement her grandfather once made:
“Come back to this room once you’re grown up.”
Using this cryptic message, Horikawa and Matsukura begin investigating the safe and the circumstances surrounding it.
Players can experience the complete chapter through the official Steam page.
Players Take an Active Role in Solving Mysteries
Unlike conventional visual novels that primarily emphasize reading dialogue and selecting responses, Seasons of Books and Keys incorporates interactive investigation into its storytelling.
At important moments, players assume the role of Jiro Horikawa and must determine solutions themselves.
This approach encourages players to examine available information, interpret clues, and develop conclusions as the narrative progresses.
According to the developers, the interactive structure is central to the game’s identity as a “drama-like adventure.”
Drama-Like Adventure Combines Literature and Interactive Entertainment
Shueisha Games and iMel describe their approach as a blend of traditional literary storytelling and cinematic presentation.
The format combines reading, visual storytelling, voice performances, and player interaction to create an experience resembling a self-contained television drama.
Rather than focusing exclusively on puzzles, the game also emphasizes character relationships, emotional developments, and subtle changes in dialogue.
The developers aim to preserve the atmosphere of Yonezawa’s original writing while introducing interactive elements that distinguish the adaptation from its literary source.
Main Characters and Japanese Voice Cast
Three central characters drive the opening chapter.
Jiro Horikawa, voiced by Kazuki Ura, is a trusting student with strong observational abilities. His willingness to help others frequently draws him into unusual situations.
Shimon Matsukura, voiced by Yuichiro Umehara, is a sarcastic, mature student whose friendship with Horikawa repeatedly leads to unexpected mysteries.
Mari Urakami, voiced by Arisa Sakuraba, is a third-year student and former library committee member who asks the two boys to investigate her grandfather’s locked safe.
Their interactions establish the foundation for the game’s mystery-driven narrative.
Adaptation Draws From Award-Winning Author Honobu Yonezawa
Seasons of Books and Keys is based on the first novel in Yonezawa’s Library Committee Series, which has surpassed 400,000 copies in cumulative circulation.
The series also includes a second volume, Seasons of Bookmarks and Lies.
Yonezawa began his literary career in 2001 with Hyouka, which received recognition at the Kadokawa Gakuen Novel Prize. The resulting Kotenbu Series later inspired anime, manga, and live-action adaptations.
His other literary achievements include the Mystery Writers of Japan Award in 2011, the Yamamoto Shugoro Award in 2014, and the prestigious Naoki Prize in 2022 for The Samurai and the Prisoner.
His Shoushimin Series also received the Yoshikawa Eiji Bunko Prize in 2025.
Seasons of Books and Keys Release Platforms and Languages
Shueisha Games plans to release the single-player adventure for Nintendo Switch and PC through Steam during winter 2026.
The game will support Japanese, English, Traditional Chinese, and Simplified Chinese.
Pricing and age-rating information have not yet been announced.
Development is being handled by iMel Inc., a Japanese studio specializing in narrative adventures and visual novels using its multiplatform Artemis Engine.
The studio’s previous work includes Tanetsumi no Uta, Lilac, The Stella of the End, and ATRI -My Dear Moments-.
New Demo Preview Video Available
Alongside the playable demo, Shueisha Games has published a preview video highlighting portions of the opening chapter and introducing the game’s visual presentation.
The demo digest video provides an overview for players interested in the title before trying it themselves.
Steam Demo Offers Early Look at Upcoming Mystery Adventure
With its combination of literary adaptation, interactive investigations, and character-focused storytelling, Seasons of Books and Keys introduces a different approach to mystery adventure games.
The complete first-chapter demo allows players to evaluate the experience ahead of its planned winter release on Steam and Nintendo Switch, while providing an early introduction to Yonezawa’s established fictional world.
Nicholas Sparks is an award-winning American writer whose bestselling novels have captivated readers for decades. Renowned for his emotional storytelling and timeless themes of love and hope, he remains one of the most influential authors in modern romance literature.
