笑わない数学者

Saikawa and Moe are invited to legendary mathematician Tennouji Shouzou's Christmas party in his mansion Mitsuboshikan. While the guests are in the mansion's planetarium, the huge Orion statue in front of the mansion vanishes and the professor challenges his guests to solve this mystery. When the statue appears again later, the corpse of a guest who was supposed to have been in her room is found in front of it, while another corpse turns up in her room...

冷たい密室と博士たち

Assistant professor Kita Hokuto invites his friend Saikawa Souhei and consequently Nishinosono Moe to the cyrogenic research facility he is working at. In the cyrogenic laboratory a murder happens. Despite all surveillance during the experiment, two students are found dead in a complete locked room situation. How did the culprit enter the room and how did he escape when even the two victims could not have entered the room in the first place?

すべてがＦになる

After being accused of murdering her parents at the age of 14 and considered as certifiably insane due to her multiple personality disorder, computer scientist and overall genius Magata Shiki retired from the world and lives in her own little locked room in the Magata research facility on an isolated island. 2 doors separate her from the rest of the facility. The inner one can only be opened with her admission while the outer door can only be opened by the other facility members and she has not left her space for 15 years. When engineering assistant professor Saikawa Souhei and his student and his former professor's daughter Nishinosono Moe request a meeting with professor Magata in this threefold locked room, a corpse wearing a wedding dress advances out of the room and what is left in there is a computer displaying the incomprehensible message 'all becomes F'...

そして二人だけになった

Teshigawara Jun, a famous blind scientist and his female assistant Morishima Yuka, three other scientists and one doctor plan on spending time gathering data in a concreted shelter located in one of the pillars maintaining the world's biggest oversea suspension bridge. One day after they arrived and settled in an earthquake happens which causes the security system to lock up the whole complex. On top of that the communication system is found destroyed and the six find themselves in a complete locked-room situation. And of course, murder after murder happens until only Teshigawara and Morishima are left...