Left alone on a snow-covered Christmas night, a teenage girl finds herself in a situation that's anything but festive. She's in a decorated home, but her strict parents have banished the joy of the season. As the night deepens, the dogs' barks become more frequent, echoing through the silent, snow-laden landscape. A strange feeling of something unseen lurking outside the window intensifies, the darkness seeming to press against the glass. Then, a plastic candle shatters violently without warning, the sound reverberating through the house, leaving her to wonder: was it just a static discharge, or had something already entered the house?