A group of kids finds old research notes about a local legend and stumbles into a horror that was already waiting for them. The film doesn't waste time on jump scares or explanations, it builds dread through what the characters discover about people who came before them, and what that discovery costs them. Mystery horror that actually earns its ending, grounded in the specific terror of learning too late that some doors shouldn't be opened.
Five high school folklore club members stumble onto something they shouldn't while preparing for their school's culture festival. Among old research notes left by a former club member, they find documentation of a local legend that eerily mirrors "Ao Oni," a creepy indie game that's become an internet phenomenon. Curious about the connection, they track down the game's creator for an interview. Then he dies under impossible circumstances. What started as a fun research project spirals into genuine terror. Trapped within the school building, the group realizes the boundaries between urban legend, internet folklore, and reality are collapsing. Something ancient wakes up in the mountain forest beyond their town, and it's drawn them into its game. As doors seal shut and the atmosphere thickens with dread, they must uncover the truth behind the Ao Oni legend before becoming its next victims. This is horror that builds from curiosity into claustrophobic nightmare, where the power of belief and collective fear become very, very real.