Her father bulled the bike out of the wallow and gave chase up the next dune, a massive six-hundred-foot mountain of red sand.

Kara reached the crest first with Habib, slowing slightly until she could see what lay beyond. And it was lucky she had. The far side of the dune fell away as steeply as a cliff, ending in a wide plain of flat sand. She could have easily tumbled tail over head down the slope.

Habib waved for her to stop. She obeyed, knowing better than to proceed. She idled her bike. Stopped now, she felt the heavy heat drop like a weight on her shoulders, but she barely noticed. Her breath escaped her in a long awed sigh.

The view beyond the dune was spectacular. The sun, near to setting, tempered the flat sand to sheer glass. Heat mirages shimmered in pools, casting an illusion of vast lakes of water, a false promise in an unforgiving landscape.

Still, another sight held Kara transfixed. In the center of the plain, a lone funnel of sand spiraled up from below, vanishing into a cloud of dust far overhead.

A sand devil.

Kara had seen such sights before, including the more violent sandstorms that could whip out of nowhere and vanish just as quickly. Still, this sight somehow struck her deeply. The solitary nature of this tempest, its perfect stillness in the plain. There was something mysterious and foreign about it.

She heard Habib mumbling beside her, head bent, as if in prayer.

Her father joined them then, drawing back her attention. “There she is!” he said, panting and pointing at the base of the steep slope.

The oryx struggled across the open plain of sand, limping badly now.

Habib held up his hand, stirring out of his prayer. “No, we go no further.”

Her father frowned. “What are you talking about?”

Their guide kept his gaze ahead. His thoughts were hidden behind dark Afrika Corps goggles and a woolen Omani headcloth, called a shamag.

“We go no further,” Habib repeated thickly. “This is the land of the nisnases, the forbidden sands. We must turn back.”

Her father laughed. “Nonsense, Habib.”

“Papa?” Kara asked.

He shook his head and explained, “The nisnases are the bogeymen of the deep desert. Black djinns, ghosts that haunt the sands.”

Kara glanced back to the unreadable features of their guide. The Empty Quarter of Arabia, the Rub‘ al-Khali, was the world’s largest sand mass, dwarfing even the Sahara, and the fantastic tales flowing out of the region were as many as they were outlandish. But some folk still held these stories to be true.

Including, apparently, their guide.

Her father throttled down his bike’s engine. “I promised you a hunt, Kara, and I won’t disappoint you. But if you want to turn back…”

Kara hesitated, glancing between Habib and her father, balanced between fear and determination, between mythology and reality. Here in the wilds of the deep desert, all seemed possible.

She stared at the fleeing animal, limping across the hot sands, every stride a struggle, its path etched in pain. She knew what she had to do. All this blood and agony had started for her benefit. She would end it.

She pulled up her sand scarf and gunned her engine. “There’s an easier way down. Off to the left.” She rode along the ridgeline, heading toward a more gentle section of the dune face.

There was no need to glance over her shoulder to feel her father’s wide smile of satisfaction and pride. It shone on her as bright as the sun. Still, at the moment, it offered no real warmth.

She stared out across the plain, past the lone oryx, to the solitary spiral of sand. While such sand devils were commonplace, the sight still struck her as strange. It hadn’t moved.

Reaching the gentler slope, Kara tilted her bike down toward the flat plains. It was steep. She and her cycle skated and skidded down the face, but she kept the bike stable on the loose sand. As she struck the rough plain, her wheels bit with the firmer traction, and she sped away.

She heard her father’s bike at her heels. The sound reached their quarry, too. The oryx’s pace increased with an agonized toss of its head.

It was less than a quarter mile off. It would not be long. On level ground, their ATVs would ride the animal down, and a quick, clean shot would end its misery, end the hunt.

“She’s going for cover!” her father called to her, pointing an arm. “Making for the sandstorm!”

Her father shot past her. Kara gave chase, bent low. They pursued the wounded creature, but desperation gave it swift speed.

The oryx trotted into the storm’s edge, heading toward its center.

Her father cursed thickly but continued racing ahead.

Kara followed, dragged in her father’s wake.

Nearing the dust storm, they discovered a deep hollow in the sand. Both bikes braked at the lip. The dust devil rose from the hollow’s center, as if it were burrowing into the desert, casting sand high into the air. The dust column had to be fifty yards across, the bowl a good quarter mile.

A smoking volcano in the sand.

Traces of blue energy laced through the devil with unnervingly silent crackles. She could smell the ozonelike odor. It was a phenomenon unique to the sandstorms of the dry desert: static electricity.

Ignoring the sight, her father pointed to the bottom of the bowl. “There she is!”

Kara looked down. Limping across the floor of the hollow, the oryx made for the thicker dust, the twisting cyclone near the center.

“Loosen your rifle!” her father called.

She remained frozen, unable to move.

The oryx reached the edge of the devil, legs shaking, knees buckling, but it fought for the denser cover of the swirling sand.

Her father swore under his breath and dove his bike down the slope.

Fearful, Kara bit her lower lip, pushed her cycle over the edge, and headed after him. As soon as she dipped down, she felt the static electricity trapped in the hollow. The hairs on her skin crackled against her clothes, adding fuel to her fear. She slowed, her rear tires sinking into the sandy slope.

Her father reached the bottom and spun the bike to a stop, almost toppling it over. But he kept his seat, twisting around with the rifle on his shoulder.

Kara heard the loud crack of his Marlin rifle. She stared toward the oryx, but it was already into the dust storm, a mere shadow now. Still, the shadow lurched, falling.

A kill shot. Her father had done it!

Kara suddenly felt a surge of foolishness. She had let her fears control her and had lost her place in the hunt. “Papa!” she called out, ready to praise him, proud of his dogged pragmatism in this hunt.

But a sudden scream strangled any further words. It came from the sand devil, issuing as if from some dark hell, a horrible cry of agony. The dark shadow of the oryx thrashed in the heart of the devil, blurred by the whirling sand. The agonized wail tore from its throat. It was being slaughtered.

Her father, still straddling the cycle, struggled to get his vehicle turned around. He stared up at her, eyes wide. “Kara! Get out of here!”

She couldn’t move. What was happening?

Then the wailing cry cut off. A horrible smell followed, the stench of burning flesh and hair. It rolled up and out of the hollow, cresting over her, gagging her. She saw her father still fighting his bike, but he had wallowed his wheels. He was stuck.

His eyes found her still frozen in place. “Kara! Go!” He waved an arm for emphasis. His tanned face was deathly pale. “Honey, run!”

Then she felt it. A stirring in the sand. At first it was just a gentle tug, as if gravity had suddenly increased. Sand particles began to dance and tumble down, quickly becoming rivulets, flowing down in a curving path, heading toward the sand devil.

Her father felt it, too. He gunned his engine, wheels spinning in the sand, casting up flumes of dust. He screamed at her, “Run, goddamnit!”

This shout jolted her. Her father seldom screamed—and never in panic.

She kicked up her engine, strangling the throttle. She saw to her horror that the dusty column had grown wider, fed by the inexplicable currents in the sand. It stretched toward where her father remained bogged in the sand.

“Papa!” she cried to him in warning.

“Go, child!” He finally freed his cycle by sheer force of will. Straddling the bike, he chased the cycle around, chewing up sand.

Kara followed his example. She swung around, gunned her engine, and fled back up the slope. Beneath her bike, the sand sucked at her, as if she were in a whirlpool, being drawn backward. She fought the sands with all her skill.

Finally reaching the bowl’s rim, she glanced over her shoulder. Her father was still near the bottom, his face muddy with sand and sweat, eyes squinted in concentration. Over his shoulder, the swirling sand closed in, towering, sparking with traceries of static electricity. It covered the entire floor.

Kara found herself unable to look away. At the heart of the dust devil, a darkness grew, spreading wider and growing blacker, more massive. The spats of static electricity did little to illuminate it. The scent of burned flesh still tinged the air. The prior warning of their guide filled her heart with terror.

Black ghosts…the nisnases.

“Papa!”

But her father was mired in the deeper, stronger currents of the whirlpool, unable to escape. The column’s edge brushed over him as it grew and spread. His eyes met hers, frantic not for himself, but for her.

Go, he mouthed—then he was gone, vanished into the darkness that filled the devil.

“Papa…!”

A horrible scream followed.

Before she could react, the column of sand exploded outward with blinding force. She was ripped from her seat and tossed high in the air. Tumbling, she toppled end over end. Time stretched until the ground rose up and struck her. Something snapped in her arm, a flash of pain that was barely noted. She rolled across the sand, coming to a stop facedown.

She lay there for several breaths, unable to move. But fear for her father rolled her on her side. She stared back toward the smoking volcano in the sand.

The devil was gone, snuffed away. All that was left was a smudgy dustiness hanging in the air. She fought to sit up, gasping and cradling her injured arm. It made no sense. She stared in all directions.