After moving into the quiet town of Hinamizawa, Maebara Keiichi spends his days blissfully in school often playing games with his local friends. However, appearances can be deceiving. One fateful day, Keiichi stumbles upon news of a murder that had occurred in Hinamizawa. From this point on, horrific events unfold in front of Keiichi, as he soon learns his close friends may not be all that they seem.

Moscow. High rise. Here, on the 12th floor, is the office of the call center "Online Store for Adults". One morning, twelve people who are in the office suddenly find out that there is a bomb in the room. The voices of the unknowns who introduced themselves as Dad and Mom threaten to blow it up at any time if the hostages do not follow their instructions. While the countdown is going on, they will have to experience the absolute power of invisible sadists and learn something about each other’s life that they did not even suspect.