Housemaid Sarah Miller was pouring wine at the banquet table when her eight-year-old son appeared beside her, clutching his blue lunchbox.

The heavy, stale air of the tunnel was instantly charged with electricity.

I stared at Vincent, my mind struggling to process how he had appeared behind the mercenaries.

"How did you get here?" I gasped, taking his offered hand. His grip was warm and grounding, pulling me back from the edge of absolute panic. "You locked yourself in the library!"

"I did," Vincent nodded grimly, keeping his voice to a harsh whisper. "But my grandfather didn't just build one exit from the panic room. The bookshelf door you used leads to the servant's quarters. There's a secondary hatch beneath the desk that drops into the sub-basement. I flanked them."

He quickly knelt beside the fallen mercenaries, stripping them of their extra magazines and tossing one of the suppressed submachine guns to me.

"I still don't know how to use this, Vincent," I protested, my hands shaking as I caught the heavy weapon.

"Safety off, point, and pull the trigger," Vincent instructed ruthlessly. "You just shot a man in the dining room, Sarah. You know how to survive."

He turned to Mrs. Gable, who was trembling against the stone wall.

"Mrs. Gable, take Toby," Vincent ordered softly. "Follow the tunnel back to the sub-basement hatch. Lock yourselves in the boiler room. It's reinforced steel. Do not come out until you hear my voice."

"No!" Toby cried, gripping my apron tightly. "I'm staying with Mom!"

I knelt down, grabbing Toby by his small shoulders, forcing him to look into my eyes.

"Toby, listen to me," I pleaded, fighting back tears. "You are the bravest boy I know. But right now, Mommy needs you to protect Mrs. Gable. Can you do that for me? Can you be my brave knight?"

Toby sniffled, looking at the terrified older woman, then back at me. He nodded slowly, his little jaw setting with a fierce determination that broke my heart.

"I'll protect her, Mom," Toby whispered.

I kissed his forehead, lingering for a second, terrified it might be the last time.

Mrs. Gable took Toby's hand, and the two of them disappeared back into the darkness of the tunnel.

I stood up, gripping the submachine gun, and turned to Vincent.

"Rosalind is outside the library," I said, my voice hardening. "She has her men setting up a breach."

"I heard the radio transmission," Vincent said, his eyes darkening with lethal intent. "They think I'm still locked inside. They're going to blow the heavy doors, exposing themselves in the main hallway."

He checked the magazine of his stolen weapon.

"We are going to hit them from behind while they're focused on the breach," Vincent explained rapidly. "But we have to move now. If they blow the doors and find the room empty, they'll realize I'm in the walls and flood the tunnels with gas."

We moved quickly past the tripwire, navigating the winding stone passages until we reached a heavy wooden door that led up to the grand foyer's coat closet.

Vincent pressed his ear against the wood, listening intently.

Muffled shouts and the heavy thud of equipment being moved echoed through the wood.

"Set the charges!" a harsh voice yelled in the hallway outside. "Rosalind wants him dead before Marco's reinforcements arrive!"

"They're rigging the library doors," Vincent whispered, turning to me. "When I kick this door open, do not hesitate, Sarah. Lay down covering fire on the men near the library. I'll take out the guards securing the perimeter."

I nodded, my throat too dry to speak. I clicked the safety off on the submachine gun, my finger resting heavily on the trigger.

Vincent held up three fingers.

Three.Two.One.

Vincent kicked the closet door with explosive force.

The heavy wood splintered, bursting outward into the grand hallway.

The scene outside was chaos. Six heavily armed Falcone mercenaries were clustered around the massive oak doors of the library, frantically wiring blocks of C4 to the hinges.

Standing twenty feet back, sheltered behind a marble pillar, was Rosalind, shouting orders.

"Ambush!" one of the mercenaries screamed as we burst from the closet.

I didn't freeze. I raised the heavy weapon, closed my eyes for a fraction of a second, and squeezed the trigger.

The submachine gun roared, the recoil violently pushing me backward. I sprayed a wide arc of suppressed gunfire toward the men at the library doors.

It was inaccurate, messy, and desperate. But it was completely unexpected.

Two of the mercenaries wiring the explosives were hit, collapsing against the heavy doors. The others scrambled for cover, their attention entirely diverted from the breach.

Vincent moved with terrifying precision. He stepped out from the closet, firing short, controlled bursts from his own weapon. He dropped three guards in less than two seconds, his aim flawless.

"Kill them!" Rosalind shrieked from behind the pillar, realizing her trap had failed completely.

The remaining mercenary, a massive man with a scarred face, raised his assault rifle, aiming directly at me as I struggled to control the recoil of my weapon.

Before he could fire, the heavy oak doors of the library—the very doors they were trying to blow up—suddenly slammed open from the inside.

The mercenary froze in shock.

Standing in the doorway of the library, holding a massive, antique shotgun, was not a Falcone guard.

It was Marco.

Vincent's loyal captain had arrived.

Marco didn't hesitate. He racked the shotgun and fired a devastating blast at point-blank range. The mercenary was thrown backward, crashing into a priceless Ming vase, dead before he hit the ground.

"You're late, Marco," Vincent yelled over the ringing in our ears, stepping forward to secure the hallway.

"Traffic was murder, Boss," Marco grinned grimly, stepping out of the library, flanked by a dozen heavily armed, loyal Hale syndicate soldiers.

The tide had turned instantly. The hunters were now the hunted.

"Secure the perimeter!" Marco ordered his men. "Wipe out any Falcone trash left on the grounds!"

The soldiers fanned out, moving with military precision to clear the rest of the mansion.

I lowered my weapon, my entire body trembling as the immediate threat vanished. We had won. The estate was secure.

Vincent walked over to me, gently taking the submachine gun from my shaking hands.

"You did it, Sarah," Vincent said softly, a profound respect in his eyes.

"Where is Rosalind?" I asked, looking frantically toward the marble pillar where she had been hiding.

The space behind the pillar was empty.

A smear of blood trailed away from the column, leading toward the grand staircase.

"She's running for the roof," Marco reported, checking the blood trail. "The Falcones have a helicopter on standby for extraction."

"She doesn't leave this estate alive," Vincent snarled, his eyes burning with vengeance for his murdered best friend.

He turned and sprinted toward the grand staircase, taking the steps two at a time.

"Vincent, wait!" I shouted, dropping the gun and running after him.

I didn't care about the danger anymore. This woman had orchestrated my husband's murder. She had destroyed my family for her own ambition. I wasn't going to let her escape into the night.

We raced up three flights of stairs, following the frantic, bloody trail left by Rosalind.

We burst through the heavy metal door leading to the mansion's expansive flat roof.

The storm was raging violently, thunder shaking the very foundations of the house. The rain was blinding, whipping across the roof in freezing sheets.

Standing near the edge of the roof, desperate and cornered, was Rosalind.

She held a small remote control in her bloody hand.

And hovering fifty feet above the estate, shining a blinding spotlight down on the roof, was a massive, unmarked black helicopter.

A rope ladder dropped from the chopper, swaying violently in the storm winds.

"It's over, Rosa!" Vincent roared over the sound of the helicopter blades, raising his weapon. "You have nowhere left to run!"

Rosalind laughed hysterically, blood pouring from a graze on her side.

"You think you've won, Vincent?!" Rosalind screamed, her voice cracking with manic desperation. "You think securing this house means you beat my father?!"

She held up the small remote control.

"You're so obsessed with loyalty, you never saw the real trap!" Rosalind shrieked.

I stared at the remote, my blood running cold. It wasn't a helicopter signal.

"What is that?" Vincent demanded, his gun unwavering.

"The offshore routing numbers weren't the only thing Thomas found out before I killed him," Rosalind smiled, a chilling, venomous expression. "He found out where my father planted the fail-safe."

She pointed the remote directly at me.

"Did you really think I hired the widow just to keep an eye on her?" Rosalind mocked, her eyes wide and crazy. "I hired her because she was the perfect insurance policy."

She pressed the button.

Nothing exploded. No alarms blared.

But my cell phone, tucked deep in my apron pocket, suddenly began to ring.

It was a sharp, piercing ringtone I had never heard before.

I pulled the phone out with trembling fingers. The screen was flashing a bright, pulsing red skull.