32 Weeks Pregnant, I Watched My Husband Bring His Mistress to Christmas—Then I Said, “Since You Brought Someone, I Brought Someone Too.”

My daughter gave a sharp, agonizing kick against my ribs, as if sensing the panic flooding my bloodstream.

I looked across the ballroom. Detective Mercer was standing near the central archway, his eyes darting toward the floorboards. He smelled it too. Our eyes met, and with a subtle tilt of his chin, he motioned toward the service corridor behind the grand staircase.

"Excuse me, Charles," I murmured to my father-in-law, pressing a gentle kiss to his cheek. "I need to visit the powder room."

"Take your time, my dear," Charles said affectionately.

I turned on my heel and walked away. Behind me, Matthias tried to follow, but an influential venture capitalist intercepted him, clamping a hand on his shoulder to discuss stock evaluations. I saw the raw, cornered panic in Matthias’s eyes as he was trapped by the very society he had tried so desperately to impress.

I slipped through the green velvet curtains into the service corridor.

The air here was freezing, devoid of the festive warmth of the gala. The bare plaster walls echoed with the hum of the estate’s industrial generators. Mercer was waiting for me near the service elevator, pulling a Glock from his shoulder holster and checking the slide with a muted click.

"Mrs. Dre," Mercer said, his voice flat and authoritative. "We have a problem."

"The solvent," I said, catching my breath against the wall. "It’s in the vents."

"My tech outside just intercepted an encrypted radio burst originating from the lower grounds," Mercer said. "Someone just activated a remote secondary receiver. This isn't just an insurance scam, Serena. They aren't trying to cause a localized fire in the archives."

"What do you mean?"

"The quantity of accelerant listed on those shipping manifests you brought me? If that detonates in the enclosed space of an old stone foundation, it will collapse the entire central structural support of this mansion. The library, the ballroom, the conservatory—everything falls into the cellar."

My heart hammered against my ribs like a caged bird. "My husband told me it was about the Hensley acquisition. He said Fiona was handling communications."

"Fiona Vale isn't a PR consultant," Mercer said grimly, looking toward the cellar door at the end of the hall. "Her real name is Fiona Vance. No relation, thank God. She spent four years in federal prison for orchestrating corporate arson in Chicago before changing her identity. Your husband didn't hire her to manage PR. He hired an executioner."

"Or she hired him," I whispered, the puzzle pieces clicking together in a terrifying new shape. "Matthias is an arrogant coward. He’s obsessed with status, but he doesn't have the stomach for real violence. He thinks this is a controlled burn. He thinks the fire will start slowly in the storage unit after everyone leaves, giving him an alibi."

"Which means," Mercer finished my thought, "he doesn't know he's being set up to die with the rest of them."

A sudden sound shattered the silence—a sharp, muffled shriek followed by the thud of a body hitting the floor behind the heavy steel fire door labeled *Boiler Room Access*.

Mercer raised his weapon instantly. "Stay behind me."

"I'm coming with you," I said, slipping off my high heels and holding them in one hand, standing barefoot on the cold concrete. "I have the emergency medical override key for the estate's fire suppression system. Charles gave it to me when we were married. Without it, you can't shut off the intake valves."

Mercer looked at my swollen stomach, then into my eyes. He saw the trauma nurse who had spent nights stitching up gunshot wounds while sirens wailed in the dark.