The guard’s grip on Kiara’s arm tightened, his fingers digging into her skin like metal clamps. "Get this street kid out of here," he barked, pulling her backward. "She’s disrupting Mr. Alliance’s schedule."

"She stays with me," Marco said, his voice flat and dangerous. "And if you fire a single shot, I’ll drop this key over the edge of this building. It’s fifty stories down to the concrete. Good luck finding a piece of silver that small in the sewers."

Viktor’s eyes narrowed. He looked at the edge of the roof, then back at Marco’s steady hand holding the silver key over the dizzying drop.

"You are a businessman, Marco," Viktor said smoothly, though his finger twitched on the trigger of his submachine gun. "You know when a venture is a total loss. The girl is nothing to you. A street rat. Why die for her?"

"Because she saved my life today," Marco replied. "And my father always said that a debt to a savior must be paid in full."

With a sudden, explosive movement, Marco didn't throw the key—he threw a heavy iron fire extinguisher he had kicked loose from the wall moments before. It crashed directly into the chest of the nearest operative, discharging a cloud of white chemical retardant.

"Go!" Marco yelled.

He fired three rapid shots, forcing Viktor to dive for cover behind a concrete ventilation duct.

Marco grabbed Kiara and Helena, dragging them toward a window washing platform suspended from the side of the building. It was a metal cage, meant for maintenance, hanging precariously over the abyss.

"Get in!" Marco ordered.

They scrambled onto the metal mesh floor. Marco slammed his hand onto the emergency release lever. The heavy steel cables shrieked as the platform dropped rapidly, plunging them down the side of the building just as a hail of bullets sparkled against the concrete wall above them.

The descent was terrifying. The wind roared in Kiara's ears as they plummeted past thirty floors, then twenty, before the automatic emergency brakes caught with a violent, bone-rattling jar.

They bounced violently, suspended fifteen floors above the street.

"We have to climb through the window!" Marco said, using the butt of his gun to smash the thick double-paned glass of an office unit. He cleared the jagged shards and pulled Kiara through first, then helped Helena, whose breathing was shallow and ragged.

They were inside a vacant, half-renovated corporate office. Dust covered the bare concrete floor.

"We don't have much time," Helena gasped, clutching her chest. "Viktor will have men on the ground. They have local police scanners. They know who we are now."

"We're going to my private airfield," Marco said, pulling out a backup encrypted phone. "I have a Gulfstream fueled and ready for a flight to Geneva. We’ll be safe there."

"No," Helena said, her voice filled with an ancient authority. "Geneva is where Viktor’s banking partners live. If you go there, you walk into a trap. We must go to Egypt. To the Port of Safaga. The black sand."

Kiara looked at her grandmother. "Grandma, why? What is under the water?"

Helena took a deep breath, her dark eyes reflecting the fading light of the afternoon. "Forty years ago, during the height of the Cold War, a Soviet research vessel carrying a classified biological and chemical compound sank in the Red Sea. It wasn't an accident. Your grandfather, a marine engineer from Syria, sabotaged the ship to prevent the weapon from being deployed. He died doing it."

She looked at the silver key in Kiara’s hand.

"Before he died, he sealed the cargo hold with a specialized hydraulic lock. He created two keys. One was given to Marco’s father, who funded the operation. The other was lost. But the lock was designed with a fail-safe. It requires the bio-signature—the blood—of his direct descendants to open it. Viktor doesn't want the gold, Kiara. He wants the weapon. He wants to harvest the pathogen to sell to the highest bidder on the black market."

Kiara stared at the key. It felt heavier now, loaded with the weight of thousands of lives.

"And if they get me?" Kiara whispered.

"They will drain your blood to override the lock," Helena said bluntly, her voice devoid of any comfort. "They don't need you alive, Kiara. They only need you warm."

Suddenly, the elevator at the end of the hall dinged.

The digital floor indicator flashed. Someone was coming up.

"They're here," Marco said, his face darkening. "We don't have time for the airfield. We need to disappear into the city first."

"I know a place," Kiara said, her eyes flashing with a sudden, street-smart determination. "The old train yard in the north zone. Nobody goes there. Even the police are afraid of it. We can hide there until dark."