I wait until the priest has turned his back. The moment he has, I make for the grand organ, its burnished pipes looming high above me as I come to stand in front of it. I glance quickly behind me to ensure, once more, the priest is not looking. He is occupied by one of the tapestries on the far wall. The time, the time! It presses on me, causing my fingers to fumble as I reach for the scroll, slotted in between two of the organ's keys.

The final clue. Why, oh why had I ever chosen to go down this path? I am arrogant, that is why. I always think myself far above others. And it has led to this-led to me creating a trail straight to the most powerful invention ever imagined, the greatest weapon mankind will ever have.

I designed this trail to be impossible, to make sport of men who thought they could ever be as clever as me. But of course, I could never resist taking risks to prove myself clever. I made this mystery solvable-but only, I believed, to myself. What I have failed to acknowledge is the inexplicable phenomenon known as teamwork. Such a simple, unassuming practice. Because of it, however, my fellow human beings may, in fact, have a chance in attaining what must never be attained.

I aim to correct that. My invention must never fall into anyone's hands but my own. Even mine should not be trusted to it. In a swift movement, I have torn the scroll in half. I now place a portion of it back into the organ. The other portion-the key to solving the mystery-I stow in my bag.