CygamesPictures has released the first promotional video for "Chiikawa Movie: Ningyo no Shima no Himitsu," giving fans their first look at the upcoming film. The trailer showcases the distinctive art style of the beloved Chiikawa franchise as it delves into the "Siren arc," a story previously explored in Nagano's manga. The film promises a surreal slice-of-life experience centered around an animal cast, with the "Ningyo no Shima no Himitsu" (Secret of the Mermaid Island) title strongly suggesting a focus on mermaid themes. This adaptation marks a significant expansion for the Chiikawa universe, moving from its usual short-form content to a feature film format. While specific release details for the summer 2026 debut are still forthcoming, the PV provides a tantalizing preview of the whimsical and often bizarre world that fans have come to expect from Chiikawa.