第 12 集: 苗木在絕望與謀殺案頻傳之際，調查校長的筆記本尋找線索
2013年9月20日 播出
Naegi no longer questions whether the principal is the mastermind, but if it isn't him, who could it be? He finds the principal's digital notebook, which allows him to find clues that will be imperative in the upcoming trial. (Source: FUNimation)