Eleven-year-old Mamoru finds himself being handed over by his parents to a strange facility that certainly is not on Japanese ground. Even knowing he will return to his parents when starting middle school, he needed some time to adjust to the new environment but eventually got used to it and found new friends among the other five students in the rather unusual residental school in the midst of nowhere.
Half a year after he arrived at the facility, the students finally start to discuss various theories about why they are gathered in this building from all over the world to routinely work on the deduction workshop's assignments.
When a seventh student is announced, things start to distort like they did when another student arrived before Mamoru came and eventually disappeared without any trace. Is there really a black evil something in this facility that despises change? Everything gets out of control when the first murder happens...
