As far as I can figure they were short-eared owls. The drawings in my copy of the Sibley Field Guide to the Birds of Western North America looked just like them. They had the same dark-rimmed eyes and dusky, mottled faces. The internet, however, suggests that no short-eared owls reside anywhere near Joshua Tree, California. But none of the owls that are supposed to be native to the area look like the ones we saw. So maybe they were migrating. Or they were some other kind of owl. Or I dreamed it all. Or the owls dreamed me.

      Later A. told me that he saw them again in that same wash and that he was confident they were barn owls. Maybe so, but when they first flew over our heads and we were standing, jaws at our navels, gawking, among the willows in that wash, he had mentioned another kind of owl. A. lived for a while in Guatemala and has read almost everything. His first thought that afternoon was of the Popol Vuh, the so-called “Council Book,” which records the creation tale of the K’iche’ Maya. “Remember the owls in the Popol Vuh?” he said, still grinning. “Messengers from the lords of the dead.”

      I had skimmed it years before, or thought I had, but I didn’t remember any owls. Later I looked them up, and kept looking things up. I was curious, though that may be too polite a word for the hunger that I felt. I wanted to know where the owls would take me. I started with the Popol Vuh. I read it twice, in two translations, and I kept reading everything I could, following whatever paths opened themselves up to me. The Popol Vuh mentions four kinds of owls. Or better put, four owls. They served as messengers for the Lords of Xibalba, the Maya underworld. The Lords were a nasty bunch, devoted to the torment of humans. There were two whose work it was “to make men swell and make pus gush forth from their legs,” two who made men “waste away until they were nothing but skin and bone and they died,” two who caused men to suddenly begin vomiting blood until they died on the road as they walked.

      Xibalba was not quite Hades or Hell, but an entire dimension of terror with its own detailed geography of punishment: awful mountains and rivers of blood; a house through which a cold wind blew, “where everybody shivered”; another filled with giant, murderous bats squeaking and screaming and flying frantically about; another teeming with knives that could dart through the air without a hand to hold them; a “house of gloom” in which there was only darkness. This was not metaphor. Xibalba was a real place, somewhere in the West. You could get there through a cave or a cenote, one of the underground springs that dot the Yucatán Peninsula, or by following the “Black Road,” the dark cleft at the center of the Milky Way, all the way to the horizon.

      But the owls. They make their first appearance in the Popol Vuh when the Lords of Xibalba become annoyed with two brothers named One-Hunahpu and Seven-Hunahpu, who, like many young men, did not like to do anything but throw dice and play ball. One day the brothers were playing ball on the road to Xibalba. They were making lots of noise. The Lords, furious at this show of disrespect, dispatched the owls with a message for them, at once a summons and an invitation: “They must come here to play ball with us so that they shall make us happy,” the Lords told the owls.

      The brothers obeyed. What else could they do? The Lords of Xibalba amused themselves with a series of unpleasant tricks, like inviting the brothers to sit on a bench of burning-hot stone—they found this quite hilarious. Then they murdered them. Before they buried them, though, they took One-Hunahpu’s head and hung it from a tree that had until that day always been barren. Instantly the tree was heavy with fruit. The Lords of Xibalba issued an edict: no one should ever eat from the tree or even sit beneath it.

      Such edicts are inevitably defied. Word got around. A young girl named Xquic, which means Blood Moon, heard about the miraculous tree. Imagining that its fruit must be impossibly sweet, she decided to seek it out, to taste it. They are rare, but there are people like Xquic everywhere, fortunately, people who defy the edicts of the powerful, whose curiosity rejects all constraints. When at last she found the tree, and stood beneath it, the skull of One-Hunahpu, which still hung from its branches, asked her what she wanted.

      “These round things hanging from the branches are nothing but skulls,” it said. “You don’t really want those?”

      “Yes,” she said. “I do.”

      “Okay,” said the skull. “Just hold out your hand.”

      When she reached out her hand, the skull dribbled spit into her palm, and Blood Moon became pregnant. With twins, of course.

      This is an odd story, I know. Is it any odder, though, than the one about the god who loves us absolutely and out of incomprehensible divine love gives us not only his despised half-mortal son, whom we murder and reject, but a strange and mystical substance known as “free will,” which condemns us, by and large, to reject our creator again and again and suffer unending sorrows? Or the one in which without realizing it humankind has been riding for the last few thousand years on a clunky sort of spaceship called progress that is taking us—some of us, anyway—to a better place, in which the miracle of reason yields universal happiness, comfort, and health?

      Seeing that she was pregnant, Blood Moon’s father complained to the Lords of Xibalba that his daughter had been disgraced. They instructed him to question her and, if she refused to answer honestly, to sacrifice her to them. So when Blood Moon protested to her father that she had never slept with anyone, he brought in the owls. Kill her, he ordered them, and bring her heart to the Lords of the Dead.

      The owls carried Blood Moon off to Xibalba. As they flew, the girl was able to convince them that their orders were unjust. They would like to help, they told her, but what could they do? They had been ordered to take her heart to the Lords.

      “But my heart does not belong to them,” Blood Moon said. “Neither is your home here, nor must you let them force you to kill men.” She was persuasive, and she was right, so the owls, at her urging, rebelled. They cut into the trunk of a tree with sap that ran as red as blood. They shaped the sap into a ball, which they pinched and formed until it resembled a heart. The owls brought this heart to the Lords of Xibalba, who were satisfied that it belonged to Blood Moon. Then they flew up out of the abyss, abandoning their masters to join Blood Moon again. She would give birth to two boys, Hunahpu and Xbalanque, the trickster hero twins of Maya lore who, after many trials, would humiliate the Lords of Xibalba, avenge their father, and topple the dominion of the dead.

      This is a long way of saying that sentences are not always final. Messengers do not always obey. Owls can be dispatched with one message and return with another. A single message, no matter how apparently unambiguous, can mean more than one thing. I’m counting on it.