“Sand is a great insulator. The royal palace of Ubar is covered with sand paintings, on floors, walls, and ceilings. The mix of so much sand in the glass must ground the structure against the static bursts, protecting those inside.” She tapped her radio. “Like it has so far with Omaha, Coral, Danny, and Clay.” Painter nodded. She read the respect and trust in his eyes. She took strength from his solid faith in her. He was a rock when she needed something to hang on to. Again.

Safia turned and stared back at the long line of folk. Everyone carried a burden of sand. They made bags out of cloaks, shirts—even the children carried socks full of sand. The plan was to pour a sand path from here to the palace, where they’d shelter against the storm.

Safia lifted her radio. “Omaha?”

“Here, Saff.”

“We’re setting off.”

“Be careful.”

She lowered the radio and stepped out onto the sand-covered glass. She would lead them. Moving forward, she used a boot to spread the sand as far as it would go and still leave good insulation underfoot. Once she reached the end, Painter handed her his bag of sand. She turned and cast the new sand down the path, extending the trail, and continued on.

Overhead, the cavern roof blazed with cobalt fire.

She still lived. It was working.

Safia crept down the sandy path. Behind her, a chain grew, passing bagful after bagful from one hand to another.

“Watch where you step,” Safia warned. “Make sure sand is under you at all times. Don’t touch the walls. Watch the children.” She poured more sand. The trail snaked from the back wall, winding around corners, down stairs, along ramps.

Safia stared out at the palace. They crept closer at a snail’s pace.

Static charges lanced at them almost continuously now, attracted to their movements, stirring whatever electromagnetic field stabilized the place. But the glass on either side always drew away the charge, like a lightning rod. Their path remained safe.

Safia dumped a load of sand from a cloak, then heard a cry behind her.

Sharif had slipped several yards back on one of the sandy stairs. He caught his balance on a neighboring wall and used it to push up.

“Don’t!” Safia yelled.

It was too late.

Like a wolf on a straggling lamb, a lance of brilliance lashed out. The solid wall gave way. Sharif fell headlong into the glass. It solidified around his shoulders. His body spasmed, but there was no scream, his face trapped in glass. He died immediately. The edges of his cloak smoldered.

Children cried out and pushed their faces into their mothers’ cloaks.

Barak ran up from farther back, slipping past others, his face a mask of pain. She nodded to the women and children.

“Keep them calm,” Safia said. “Keep them moving.”

She took the next bag. Her hands shook. Painter stepped next to her, taking the bag. “Let me.” She nodded, falling back into second place. Kara was behind her. “It was an accident,” she said. “Not your fault.” Safia understood it with her head, but not her heart.

Still, she did not let it paralyze her. She followed Painter, passing another sack to him. They crept onward.

At last, they rounded the courtyard wall. Ahead the entry to the palace glowed. Omaha stood in the archway, flashlight in hand.

“I left the porch light on for you guys.” He waved them forward.

Safia had to resist the urge to run forward. But they were not safe yet. They continued at the same steady pace, rounding the iron sphere resting in its cradle. Finally, their long trail reached the entry.

Safia was allowed through first. She stepped inside and hugged her arms around Omaha, collapsing against him. He picked her up in his arms and carried her back to the main room.

She didn’t object. They were safe.

7:07 P.M.

C ASSANDRA HAD watched the procession, not moving, barely breathing. She knew to move meant death. Safia and Painter had passed within a few yards of her small glass alcove.

Painter had been a surprise. How could he be here?

But she did not react. She kept her breathing even. She was a statue. The many years of Special Forces training and field ops had taught her ways to remain still and quiet. She used them all.

Cassandra had known Safia was coming. She had mapped their progress, moving only her eyes, and had watched the very last red triangle on her tracker vanish a moment ago. She was all that was left. But it wasn’t over.

Cassandra had watched in amazement as Safia returned to the cavern from above, returning here, passing so close.

A sand trail.

Safia had discerned the only safe haven in the cavern: the large, towering building that stood fifteen yards away. Cassandra heard the others’ happy voices as they reached their sanctuary.

She remained perfectly still.

The sandy track wound only two yards from her position. Two large steps. Moving only her eyes, she watched the skies. She waited, tensing every muscle, preparing herself. But she remained a statue.

Then a bolt struck down about three yards away.

Close enough.

Cassandra sprang through the door, trusting in the old adage “lightning never strikes the same place twice.” She had nothing else to go on.

One foot touched glass, only long enough to leap away. Her next foot landed on sand. She dropped to a crouch on the path.

Safe.

She took deep breaths, half sobbing in relief. She allowed herself this moment of weakness. She would need it to steel herself for the next step. She waited for her heart to stop pounding, for the shakes to subside.

Finally, her body calmed. She stretched her neck, a cat awakening.

She took a deep breath, then let it out. Now down to business.

She stood and took out the wireless detonator. She checked to make sure it hadn’t been damaged or its electronics fritzed. All appeared in order. She tabbed a key, pressed the red button, then tabbed the key again.

A deadman’s switch.

Rather than pressing the button to blow the chip in Safia’s neck, all she had to do was lift her finger.

Prepared, she slipped her pistol from her holster.

Time to greet the neighbors.

7:09 P.M.

S EATED ON the floor, Painter stared around the crowded room. Coral had already reported and debriefed him on all that had happened, her theories, and her concerns. She now sat beside him, checking her weapon.

Across the room, Safia stood with her group. They smiled and soft laughter floated from them. They were a new family. Safia had a new sister in Kara, a mother in Lu’lu. But what about Omaha? He stood at her side, not touching, but close. Painter saw how Safia would lean ever so slightly in the man’s direction, almost touching, but not.

Coral continued cleaning her gun. “Sometimes you just have to move on.”

Before he could respond, a shadow shifted on his right, by the entryway.

He watched Cassandra step into the room. Pistol in one hand, she was calm, unconcerned, as if she had just come in from a stroll to the park.

“Now isn’t this cozy,” she said.

Her appearance startled everyone. Weapons were snatched.

Cassandra didn’t react. She still had her pistol pointed at the ceiling. Instead, she held out a familiar device. “Is that any way to greet a neighbor?” “Don’t shoot!” Painter boomed, already on his feet. “Nobody shoot!”

He even moved to stand in front of Cassandra, shielding her.

“I see you recognize a deadman’s switch,” she said behind him. “If I die, poor Dr. al-Maaz loses her pretty little head.” Omaha heard her words. He had already shoved Safia behind him. “What is this bitch talking about?” “Why don’t you explain, Crowe? I mean the transceiver is your design.” He turned to her. “The tracker is…not the bomb.”

“What bomb?” Omaha asked, his eyes both scared and angry.

Painter explained, “When Cassandra had Safia in her custody, she implanted a small tracking device. Cassandra modified it with a small amount of C4. She holds the detonator. If she lets go of the trigger, it will blow.” “Why didn’t you tell us before?” Omaha said. “We could’ve removed it.”

“Do that and it blows, too,” Cassandra said. “Unless I first deactivate it.”

Painter glared at her, then back to Safia. “I’d hoped to get you somewhere safe, then have a surgical and demolition team remove the device.” His explanation did little to quell the horror in her eyes. And Painter knew some of it was directed at him. This was his job.

“So now that we’re all friends,” Cassandra said, “I’ll ask you to throw all your weapons out into that courtyard. Everyone now. I’m certain Dr. Crowe will ensure that every weapon is accounted for. One slip and I may have to lift my finger and scold someone. We wouldn’t want that to happen, would we?” Painter had no choice. He did as Cassandra instructed. Rifles, pistols, knives, and two grenade launchers were piled into the courtyard.

As Coral threw her half-assembled gun with the others, she remained by the entry. Her eyes were on the cavern. Painter followed her gaze.

“What’s the matter?” he asked.

“The storm. It’s grown worse since your arrival. Much worse.” She pointed to the roof. “The energy is not draining fast enough. It’s destabilizing.” “What does that mean?”

“The storm is building into a powder keg in here.” She turned to him. “This place is going to blow.” 7:22 P.M.

F ROM THE second-story balcony of the palace, Safia stared with the others out at the maelstrom. The cavern roof could no longer be seen. The roiling clouds of static charge had begun a slow spin across the dome, a vortex of static. In the center, a small downspout could be seen, perceptibly lowering, like the funnel cloud of a tornado. It aimed for the antimatter lake.

“Novak’s right,” Cassandra said. She was studying the phenomenon through her night-vision goggles. “The entire dome is filling up.” “It’s the megastorm,” Coral said. “It must be much stronger than the ancient storm that triggered the cataclysm two thousand years ago. It’s overwhelming the capacity here. And I can’t help but think a fair amount of the lake water is probably destabilized like the contents of the iron camel.” “What will happen?” Safia asked.