No doubt there are a multitude of mystery readers out there who love digging into classic spy stories from the golden age of espionage. Filled with ritzy postwar ballrooms, foggy alleyways and the smell of gunpowder, these stories conjure up boatloads of thrilling nostalgia, one swishing trench coat at a time. But have you ever imagined a Cold War that plays out in both this life and the afterlife? Or contemplated world powers vying for demonic runes in their quest for influence? Both of these supernatural mysteries excel at taking a familiar genre and time period and augmenting them with just enough otherworldly elements to make each page feel new and exciting.