LDS Church (FYI: I'm an employee of the LDS Church), it was a little weird for me to read. I'd cringe every once in a while when something was mentioned that was implied about employees of the Church, some stereotype.
The author, while working as an editor at Deseret Book was challenged by a coworker to write a book (she, the challenger, was supposed to write one too, but didn't.) He'd played around with writing his own book for a while (he's published a number of collections of the writings of others.) This is his first published piece.
It's a quick read, a book like DaVinci Code (a comparison the author himself makes in the story) where a mystery it to be solved.
The author also disclosed his interest in the translation of the Book of Mormon, which he talks about in the book. That's much of the theme of the book. Translation, code breaking (as mentioned in the title), blackmail.