I knelt and studied the ground. There was a circular smudge from the toe of a shoe where someone would have stood and pivoted on one foot in the process of sitting down in the driver’s seat. The pressure had rolled over a pebble that revealed a crescent of dirt that was slightly darker than the rest around it. The print had been made before sunrise, but not my much.

And it was the only one.

At least I knew I was in the right place. The rest of the footprints had been erased in a circle around where the vehicle had been parked as though with a leaf blower, just like I had seen at the third crime scene. I didn’t have to look far to find where the air-swept path led upward toward a crest of rock shaped like the bow of a ship breaking through the mountainside.

And now I had a decision to make. I could either call this in and attempt to convince a highly motivated army of Border Patrol agents that they were looking in the wrong place or I could strike off and risk any number of bad outcomes on my own. Regardless, if my assessment of the situation was correct, Antone was already dead.

I stared uphill for a long moment before I finally started walking. I didn’t even glance back at my car, where the scanner still rested in the charger on the console. I was on my own. As I had always been meant to be.

The lack-of-tracks trail guided me only so far before vanishing, although I could still see the occasional signs of recent passage in the slightly matted clumps of wild grasses and in the bent and broken branches of the palo verdes. The only thing I could tell with any kind of certainty was that whoever had returned to the vehicle and driven it away hadn’t been dragging a makeshift travois as he had in the past. The placement of the footsteps was cautious, but not overly so. As though whoever left them had no objection to someone following his trail if they were good enough to find it, and yet at the same time was careful enough not to leave a single track with enough definition that it could later be identified and matched to him. I found this interesting and somewhat unnerving. I could only assume that suggested the killer intended to walk free when all was said and done, which was either a symptom of an overdeveloped ego or implied a different kind of resolution to the endgame than I envisioned.

I paused whenever I found anything resembling shade and drank from the rapidly warming water. It’s amazing how quickly your body temperature rises in response to the environment. I was in good physical shape, but I could barely go a quarter-mile without starting to feel like I was sweating out more fluid than I was retaining. I couldn’t imagine the prospect of attempting to cross forty miles of desert in extremes like this. I think I would have rather taken my chances swimming across the entire Gulf of Mexico.

At least I was working my way up into sharp valleys that appeared to be deep enough to offer some respite from the merciless sun. I did appreciate the fact that the rattlesnakes clung to the cover of the shrubs and were kind enough to warn me when I got too close. I was starting to get used to them, anyway. I didn’t mind them nearly as much when they weren’t striking at my face.

I picked up the trail at the mouth of a red-rock canyon barely eight feet wide before losing it altogether. It was more of a crevice than a canyon really, like the two neighboring mountains were in a constant state of flux, moving apart in increments of inches per century. The uneven ground offered bare stone upon which to tread without leaving a print, at least not one that I could detect. If I was correct, I was nearing the destination Antone had marked on his map. The biggest foreseeable problem was that I was still going to have to find the entrance to the cave. And this arroyo formed a perfect bottleneck, the kind for which the Coyote had already shown a fondness.

I drew my pistol and waited. A hawk cried as it circled over the foothills behind me. A sudden gust of wind caused pebbles to trickle down the rock walls from somewhere above.

I dropped the map on the ground and unrolled it with my foot. Yeah, I was in the right place. Somewhere on the far eastern side of this gully. I nudged a rock onto the map to hold it in place and advanced cautiously in a shooter’s stance.

The air in the arroyo was perfectly still. A feather would have fallen like a lead weight. The sound of my breathing echoed back at me from the narrowing walls. A ribbon of sand navigated the rocks underfoot where seasonal dribbles flowed. I was starting to think that I had chosen the wrong route. The rock walls constricted and it almost looked like the passage terminated in front of me. I was nearly to the terminus when I recognized it for what it was: a sharp bend to the right. Branches and random detritus had accumulated in the junction. I was just about to step over them so I could peek around the corner to my right when I heard a sound.

I stopped dead in my tracks and listened as hard as I could.

It sounded like waves washing against a beach, a slow repetitive shushing sound, but that obviously couldn’t be the case. Considering the complete absence of airflow, it couldn’t be the wind either. I thought about the rattle-less diamondbacks and ruled them out just as quickly.

Gravel skittered down the stone wall to my left. I glanced up to see a buzzard perched on a pinnacle of rock, staring down at me. It stretched its wings and settled in. I took its presence as a bad sign of what was around the corner, rather than an indication of what Mother Nature thought of my chances.

I wasn’t accomplishing anything by standing still.

I ducked and went around the bend in a crouch. My Beretta preceded me into a widened section that functioned as the junction of two more arroyos.

The shushing sound grew louder, but I still couldn’t identify it any more than I could divine its origin.

It grew louder still as I advanced, alternately scanning the area ahead of me and the canyon walls above for any sign of movement. Another fat black vulture alighted on a cholla skeleton thirty feet up to my right and tracked me with its beady eyes all the way to the fork. The branch to my left led toward the sunlight, where the rock walls petered to sandy hills bristling with cacti and yuccas. The branch to the right led into deeper shadows, at the far end of which I could see a bright sliver of sunlight where it opened onto the eastern slope. The sound was definitely coming from that direction.

I tried to picture Antone walking up here alone under the glow of the moon. A coyote howling in the distance. The faint thupp-thupp-thupp of helicopter blades to the north from the scene of a crime he had no idea had been committed. The scuffing sound of gravel underfoot. A notebook page of scribbled directions in his hand. Or maybe a GPS unit. This wasn’t a blind walk for him. He had some idea where he was going; this was just the most direct route.

Sshhuusshhuusshhuusshhuusshhuuhhrr.

I pressed onward, wary of my surroundings. The light of the opening at the far end became larger with each step, limning the rugged rock walls a pale gray. Another buzzard watched me from its perch on a jagged ledge high above me, a black silhouette against the sky.

Sshhuusshhuusshhuusshhuusshhuuhrr.

I finally smelled what had drawn the vultures. Faint, but impossible to miss if you were familiar with the scent. Simultaneously biological and metallic. A sickly taste on the back of the tongue as much as a smell, one that told me something terrible had happened here.

It was blood.

Sshhuusshhuusshhuusshhuusshhuuhrr.

The world around me lightened by degree. The smell intensified. The air started to flow. Sweat rolled down my neck and back. I had to readjust my grip on my pistol.

The dirt beneath my feet softened several feet from the outlet. I risked a glance down and saw amoeboid splotches of mud that would have already been completely dry were it not for the shadows. To my right, an arterial spatter had ascended the canyon wall nearly to the top. Another led out into the sunlight where it dotted a palo verde like little red berries. It was almost a relief to step out into the open again. Ahead of me, the foothills led downward to the stretch of desert that passed through New Mexico on the way to Texas, beyond the horizon.