At 11:20 PM on Christmas Eve, the four of us were lying in sleeping bags in the living room.

Only the red and green glow of the Christmas tree lights flickered in the darkness. The house was unnervingly quiet.

Dad's shotgun lay right next to his sleeping bag. The green light of the smart security system blinked steadily on the wall.

Sophie, dressed in her favorite unicorn pajamas, lay beside me, buzzing with excitement. "Chloe, when does the game start?"

"In ten minutes, at 11:30," I whispered. "You remember the rules?"

"I remember! Don't open your eyes, don't talk, and don't fall asleep," Sophie nodded seriously. "I can totally make it to two o'clock."

Mom shifted in her sleeping bag. "Chloe, I still think this is ridiculous," she whispered. "Lying on the living room floor because of some stranger on the internet…"

"Shh," Dad cut her off. "We already agreed. We'll do what Chloe says. It's just a few hours."

At exactly 11:30 PM, I glanced at my phone and whispered, "It's starting."

The minutes ticked by.

At first, nothing happened. I could hear Dad's heavy breathing, Mom shifting occasionally, and the tiny rustles Sophie made trying to stay still.

12:10 AM. Still nothing.

12:20 AM. Sophie was getting restless.

"Chloe…" she mumbled. "I'm cold, and the floor is hard. I wanna go back to bed."

Dad started to question it too. "Chloe, it's been almost an hour. Nothing's happening. What's the point of this game?"

He started to sit up. "That's enough. Let's go back to our rooms. We have to get up early for Christmas dinner tomorrow."

Mom began to pack up her sleeping bag. "Yeah, this floor is killing my back."

Sophie immediately chimed in. "I wanna go to my room, too!"

I was about to stop them when, suddenly…

Screee—craaape—screee…

A high, grinding screech of tearing metal echoed from the central air vent in the ceiling, as if something enormous was crawling through the narrow ductwork.

Everyone froze.

Then, a clearer sound came from deep within the fireplace.

Scrape… scrape… scrape…

Something was moving down the chimney.

Whoosh…

A shower of soot and brick dust rained down from the fireplace, sounding as loud as thunder in the silent room.

Sophie gripped my arm in terror. Mom let out a stifled scream.

"Get down!" I hissed, using all my strength to keep my voice low. "Close your eyes! Pretend to be asleep! Now!"

Dad's face was white as a sheet. He shut his eyes, his hand gripping the shotgun, the barrel aimed at the fireplace.

I cracked one eye open just a sliver, watching the fireplace.

I saw it. A long, thin, pale thing extended from the chimney.

It looked like the leg of some kind of insect, with sharp, distinct joints and a pointed claw at the end. It slowly reached out, grabbing the mantelpiece, its claw making a horrifying scratching sound against the stone.

Suddenly, the smart security panel on the wall began to flash wildly, its red light as piercing as a siren.

The system's cold, mechanical voice blared through the living room:

"WARNING. PREMISES HAVE BEEN BREACHED. WARNING. PREMISES HAVE BEEN BREACHED. UNKNOWN BIOLOGICAL ENTITY DETECTED. THREAT LEVEL: CRITICAL. EVACUATE IMMEDIATELY. WARNING. PREMISES HAVE—"

The limb extending from the chimney stopped dead, its claw digging into the mantelpiece, completely still.

As if it were waiting.

I prayed the alarm would scare the monster away.

But in the next second, the claw shot out, extending with impossible speed and precision, and slammed down on the security panel's off switch.

I watched in horror as the security system went silent.

And the thing from the chimney began to slowly, piece by piece, crawl out of the fireplace…