DO NOT OPEN IT.
You may have heard of the Necronomicon, Satan’s Bible, or the Black Codex. They are all pretenders to what the Book really is. If I had a choice in the matter, I would have burned the book and myself to rid the world of the knowledge recorded within it. However, there is a purpose to the book.
Let me tell you how the Book came to me. I worked for a company specializing in selling old and rare books. Part of our clientele were people who had inherited a book collection from an older relative and wanted to sell it off. We would appraise the books and either offer a conservative lump sum for everything or act as a broker to sell the books individually. I was nearly through cataloging this particular collection, when I found the Book. It was wrapped in paper tied with string. On the paper was a warning not to open or read until a certain date. A date well into the future. I had a job to do and a bit of paper and string wasn’t going to stop me.
The Book was … is, as you can see, rather unassuming. The cover is cloth bound, blue, worn in places but still sturdy. The pages are thick, coarse cut paper. I opened it and saw the black, delicate, sharp calligraphy unfaded by time, just as you will (heaven protect you because you must read it, I’m sorry). I started reading and reading and reading well past where I wished to stop but I was compelled to finish. When I was done, I knew things no one should know. I am so sorry that I must inflict this on another person. Just reading the Book I knew had cost me my soul. I am tainted by the book. Its forbidden knowledge craves a vessel. It promises power, control, eternal life at the low, low cost of ten easy payments of a human soul. Yours will be the first but not the last. You have to find other investors who will find more. It’s hell’s own ponzi scheme. I resisted but that is not enough to save my soul. I will be damned when judgment day comes.
There are other concerns to worry about before that happens. A conjunction of two planes of existence is coming. Something will be unleashed on our world that will end life as we know. Neither heaven nor hell alone have the power. The Book is an unspeakable fusion of knowledge from both; bound by heavenly cloth, inked with hell’s own ash. With the knowledge it contains all of creation can be protected but at the cost of –
I can not know if you are a good person, I can only hope that you will put the fate of our world above your own. The longer you have the Book the more you will be tempted to use its knowledge. I could not trust myself. So, I placed it beyond my grasp, in a time capsule sealed in concrete for a hundred years.
If you found this letter alone, not wrapped around the Book, then I have a different mission for you. Find the Book. The fate of the world depends on it.