Directed by Jiro Nagae, the new leading light of Japanese horror, this hard-hitting movie has an original script inspired by the Samejima Incident, known as the most mysterious internet urban legend of early 21st century Japan. All those who know the truth behind the incident have disappeared, and those who hear about it die, so nobody knows the facts, and nobody can find the truth. With the proliferation of social networks, and with work, study, and leisure activities now held online, the curse, and fear of it, spread like a pandemic, shaking society to its core.
Every year, Nana Sasakiand her former classmates hold a reunion of their high school music club. This year, the reunion is being held online. However, for some reason, one of them, a woman called Ayumi, doesn't show up. When the others voice their concern, Yuki and Suzu reluctantly tell them about the Samejima Incident, an urban legend which circulated on the internet 20 years earlier. Those who find the truth about it become cursed and die. Intrigued by the mystery, Ayumi, Yuki, and Suzu had visited an abandoned building said to be connected to the incident, and while they were there, Ayumi had begun acting strangely. Does the curse of the Samejima Incident really exist? As Nana and the others start to panic, the real horror begins.