CHAPTER 1

Miranda Bell rapped her knuckles against the molded plastic body of the dive light and worked the switch again. This time, the bulb lit up, shooting out a beam of white light. She worked the switch again, on and off several times, until she was satisfied that the problem had fixed itself, then slipped the pistol-shaped flashlight into a carrier on her hip.

The light, like the rest of the gear they’d rented from the dive shop in Tulum, was serviceable if somewhat antiquated. She had always used only the best equipment, sometimes field testing prototypes and cutting edge technologies unavailable to the public at large, but that had been in another life. Now she had to make do with whatever semi-obsolete, off-the-shelf equipment she could get her hands on.

She did a final head-to-toe check, then sat down at the edge of the cenote, letting her long legs dangle out over the azure water. She took a breath from the second-stage line of the regulator attached to the AL80 SCUBA bottle on her back to ensure the air was flowing, then turned and looked up at the anxious face of Charles Bell, her father.

“Don’t run off,” she quipped, before placing the mouthpiece between her teeth.

“Miranda,” he pleaded. “Just wait. Half an hour. They’ll be here.”

Miranda fought the urge to roll her eyes. Her father was just being over-protective, which was, she supposed, his job as a father, but she had no intention of waiting for his so-called marine salvage experts to arrive. Knowing Bell, they were probably some over-priced tour guides who would probably shut them down and call in the local authorities when they realized what they had found.

Sometimes he could be so clueless about the way the world worked.

What they had found, or at least what they thought they had found, was a previously undiscovered cenote, which was remarkable because the area around Tulum had been extensively explored and mapped, particularly here in the government designated archaeological preserve. The cenote was larger than some she had seen, and not as overgrown. They had stumbled across it during a hike through the forest, and at first believed they must be lost because it did not appear on the map. How this particular hole had gone unnoticed for so long was anyone’s guess, but if it was truly uncharted, there was a good chance of finding artifacts of real value inside, which was all the more reason for her to make the dive now, without waiting for the experts.

“I’ll be fine, Dad,” she assured him, and then tapped the GoPro which rested just above the top of her mask. “It’s recording, right?”

She knew it was and was only asking to distract him so he wouldn’t delay her any longer. Bell held up his tablet computer, which displayed the live video signal from the digital camera. Because she was looking at him, the screen showed Bell holding up the tablet. Some deficiency of the technology prevented the image from repeating to infinity, but the effect was surreal nonetheless. The wi-fi signal from the digital camera would be lost once she was submerged, so Bell would have to wait until she returned to see the fruits of her exploratory dive.

Miranda nodded and then inserted the mouthpiece and scooted forward, dropping down into the water. The weight of her gear bore her down quickly, but only for a second or two, just enough for her to feel the pressure against her inner ear.

Below the surface, the white limestone seemed to glow a cool blue, like some kind of weird radioactive element. The water, only slightly brackish, was crystal clear but the hole was so deep that sunlight did not reach the bottom.

She popped her ears to equalize the pressure and switched on her dive light, probing the depths of the hole. Although the entrance at the surface was only about twenty-five feet in diameter, the cenote—which had, hundreds of thousands of years earlier, been a mostly dry cavern, hollowed out of the limestone karst by geological forces—broadened out in all directions. The overhanging ceiling blocked out most of the daylight, leaving the subsurface environment in a state of perpetual gloom, broken only by the cone of illumination cast by the light in her hand. Her bubbles were glittering silvery globes racing to pool on the stone ceiling above, while she continued at a more leisurely pace in the opposite direction.

The cenote did not have a flat bottom like a swimming pool or well, but undulated in a series of upright protrusions and deep crevices. It reminded Miranda of a gigantic molar. This impression was reinforced by a brownish silt layer that covered the rises, like an accumulation of plaque on a tooth. She knew better than to disturb the silt. Doing so would raise a cloud of the fine particles, effectively rendering her blind, but she nevertheless played her light over the surfaces, looking for any hint of something that might justify temporarily sacrificing visibility.

Something glinted from a shelf of rock off to her left. She swam toward it, her pulse quickening as she imagined carefully brushing away the sediment to reveal a priceless golden artifact.

Just one would be enough to put her father back on top of his game.

But even before she uncovered it, disappointment dashed her hope. An object lay there, an artifact made by human hands, but it wasn’t made of precious metal and it wasn’t from the Maya civilization. It was a beer bottle. The glint she had seen was from the gold foil around the neck. The label was still intact, and even through the silt she could make out the word: Modelo.

Not undiscovered after all, she thought miserably, kicking back toward the center.

Still, a single piece of discarded trash did not mean the depths of the cenote had been completely plumbed. She swam in a wide circle, looking for a channel or crevasse that might take her deeper still.

After completing a full revolution around the irregular circumference, she moved toward the center and began another circuit, repeating the process in a concentric fashion until she had visually surveyed every square inch of the bottom of the cenote. She noted several deep crevasses, some that looked promising but ultimately yielded nothing of interest, not even more detritus of the modern world.

She checked her pressure and calculated that her air supply would hold out for at least another half-hour. She wasn’t deep enough to worry about decompression stops, though given her actual time at depth, it would probably be a good idea to make a slow ascent. That still left her with plenty of time to explore, but she didn’t really see the point. The cenote was, in every sense but the literal, a dry hole, and besides, her father was probably tearing his hair out. It was time to head back up.

Just for the hell of it, she decided to stretch out her ascent by swimming in a counter-clockwise corkscrew around the edge of the cavern. The change in perspective helped alleviated the boredom, but the results were no different.

She was almost back to the surface when something caught her eye, or more precisely, the lack of something. Hidden behind a tangle of roots from a tree that had infiltrated down through the ceiling, was a dark spot, like a shadow, into which the beam of her light disappeared completely. There was a void there, something she had missed during her initial descent. She swam closer and began pulling at the roots that blocked the way.

Her original assessment was correct; there was a passage behind the roots, a hollow space in the limestone big enough for her to swim into if she could clear the obstruction at the opening. She drew her knife and began sawing at the roots. They were as tough as cables but after a few minutes of dragging the blade back and forth, she succeeded in removing one. Rather than waste more time cutting, she simply pushed the others out of the way and wriggled through the resulting gap.

She knew that the safe course, the course of wisdom, would have been to simply mark the location of the passage for a future dive. That was what her father would have counseled. But her instincts told her the passage would be just another dead end. It made more sense to spend her remaining air to get a definitive answer than to raise her father’s hopes only to have them dashed again.

Her instincts were wrong.

The passage meandered for about twenty yards before turning down and opening up into another spacious cavern.

Miranda’s heartbeat quickened again as her light fell upon something that was most definitely not a naturally occurring geological feature. A large block of stone stood at almost the exact center of the cavern. Four feet wide and almost as long, relief images that were recognizable even to her relatively untrained eye as Mayan hieroglyphs adorned its length. She swam in close, keeping her gaze on the object so that the GoPro would capture every detail. There were more carvings on the sides, each a square glyph about eight inches across, no doubt some kind of religious myth or perhaps a historical record; her father would know.

She came around to the far side of the object and caught another glimmer of gold, only this time, it wasn’t foil on an old beer bottle. It was the real thing.

The regulator fell from her mouth as she went slack-jawed.

Where the central glyph ought to have been, there was instead a recess in the stone, and inset within was a shiny yellow disk the size of a salad plate. The disk was adorned with a large central glyph of a four-legged creature—a dog, if Miranda was not mistaken—and several smaller images arrayed in a circle around the outside.

She replaced the mouthpiece then drew her knife again and carefully worked the point into the carved recess behind the disk. The golden artifact shifted and then popped free. Miranda brought her free hand around to catch it, but the water slowed her reflexes. The object sank to the bottom before she could grab ahold. It landed with a thud that she could feel vibrating through the water, and threw up a murky cloud of sediment that both marked and obscured the spot where it had hit.

Miranda breathed out an irritated curse, then kicked down into the cloud to retrieve the fallen disk. If it was solid gold, it would be a lot heavier than it looked, maybe too heavy for her to get all the way back to the surface, but she wasn’t about to leave without making the attempt. She cautiously extended a hand into the silt cloud until she made contact with something solid. She curled her fingers around the object and tried to lift it.

To her complete astonishment, it came up with hardly any effort, as the murky water below her cleared, she saw why. The thing she was holding was not the golden disk, but a human skull.

She dropped it like it was a snake about to strike, and kicked away with a silent scream. As she shot up to the roof of the cavern her light played across the floor and in its beam she saw more skulls, at least two dozen of them, staring up at her with empty eye sockets.

She yelped again, her heart hammering in her chest.

Get a grip, Miranda, she told herself, taking a deep drag on her air supply to calm herself. They’re just skeletons. They can’t hurt you. They’ve been dead for centuries.

Except she was wrong about that, too. Most of the skulls lay with their disarticulated skeletons, their flesh and any garments long since decayed to nothing, but some still had ragged bits of decomposing tissue and clothing clinging to them. At least one of the corpses appeared to be wearing blue jeans and a button-up work shirt.

Miranda took another breath and decided it was time to go. This wasn’t an archaeological site anymore—it was a crime scene.

But as she turned to look for the exit, she was confronted with not one, but several passages all evenly spaced around the circumference of the room. She couldn’t tell which one she had come in through. She was having trouble counting them. There were at least ten, maybe as many as fifteen, all radiating out like the spokes of a wheel.

I am so screwed, she thought, but then shook her head. No. You’ve got this Miranda. Think.

Miranda took another deep breath... or tried to. The air didn’t seem to want to come out of the tank. She grabbed the pressure gauge, but it only confirmed what she already knew. She was out of air.

Right the first time, she thought. Definitely screwed.