When a scandal upends a famous TV mother’s life ahead of the holidays, she heads to a luxury Vermont resort for Christmas. Upon arriving, a booking error leads her to a quaint B&B owned by an astronomy teacher.

After witnessing his parents' brutal murder on Christmas Eve, Billy transforms into a Killer Santa, delivering a yearly spree of calculated, chilling violence. This year, his blood-soaked mission collides with love, as a young woman challenges him to confront his darkness.