Lisa Mishima is having problems at school and home when two mysterious boys transfer to her school; Lisa finds herself in the middle of a terrorist attack.

While the police work hard to analyse Sphinx's first attack, Sphinx uploads a new video, and they must solve the new riddle in time.

Shibazaki joins the team working on the Sphinx case; Sphinx tries to confirm suspicions of their own with their next riddle.

The investigation into the serial bombings continues; Shibazaki goes to Aomori in search of clues about who the culprits are.

While Lisa recuperates at Nine and Twelve's place, Sphinx sets another bomb and posts another riddle, but things don't go as planned this time.

Five takes over the battle of wits against Nine and Twelve while Lisa tries to find her place in their group; Shibazaki isn't happy sitting by idly.