(you sneak into the Federal Bureau of Investigation to become a spy there, and become one of the 1st division team, including Kudo.)

everyone was busy solving puzzles that had been given by someone unknown. “Even so.. what does this mean?" someone said, who was confused by the letter, the contents of the letter; 14 = (11 people + 1 person) + 2 people 15 = (11 people + 1 person) + 2 people + 1 person.

Then, Kudo spoke while holding his chin and thinking. “Aren't these 12 trusted people, Mr. Naka? Like the 12 disciples of Jesus.” then Mr. Naka spoke raised his eyebrows “12 disciples of Jesus..? Wait, why doesn't the letter directly write 12 people? But 11 + 1? Is there a traitor among us?” everyone silent. “like Judas. Traitor.” silent again, "you know.. that I suspect someone here" Kudo spoke while glance at you and smirk.