STUDIO 909 and game designer Kazuhide Oka are developing an adventure game titled Quiet Express: Cabin 909, which will be available on PC via Steam and support multiple languages including English, Japanese, Korean, Traditional Chinese, and Simplified Chinese. The game features a journey on a mysterious cabin train, where players will explore the lives of passengers and uncover the mystery of Cabin 909, which does not appear to exist. The Tokyo Game Show 2025, taking place from September 25 to 28 in Chiba, Japan, will allow attendees to experience the game. The development team includes Kazuhide Oka (scenario and development), Kohei Miyahara (art and environment models), ASAMIYA KOBO (concept key visual and character models), ruichiro (soundtrack), JEFF99 (logo art), and various translators for different languages.