This is a story about a nearly 100-year-old book, bound in red leather, which has spent the last quarter century secreted away in a bank vault in Switzerland. The book is big and heavy and its spine is etched with gold letters that say “Liber Novus,” which is Latin for “New Book.” Its pages are made from thick cream-colored parchment and filled with paintings of otherworldly creatures and handwritten dialogues with gods and devils.If you didn’t know the book’s vintage, you might confuse it for a lost medieval tome. And yet between the book’s heavy covers, a very modern story...