According to the Talmud, the demons are more numerous than we are. “They stand over us like mounds of earth surrounding a pit.” Rav Huna teaches that “each and every one of us has a thousand demons to his left and ten thousand to his right.” Abba Binyamin tells us that “if the eye had the power to see, no creature would be able to withstand the demons.” Fourteen centuries before Lovecraft, the Talmudists knew that what we see is only the tiniest portion of what’s really there, and the rest is monsters. Our ordinary world, the one in which we work and fall in love and watch TV—it’s thinner than paper, and the demons pour through it in hordes. This planet isn’t our home; it’s a hive. And though seeing the demons is fatal, the rabbis tell you how it may be done. Scatter a circle of fine black ashes around your bed at night, and in the morning, you will see their footprints, their claws like a rooster’s, their terrible number. What they don’t tell you is how you will ever sleep comfortably again.