When 17-year-old Maddy Andrews discovers her seemingly perfect new stepsister has a sinister dark side, she must find a way to protect herself, and her mother–or risk becoming the latest in a long line of victims.

A young woman enters a Christmas tree decorating contest to honor the memory of her mother, only to discover that the competition includes her recently-widowed high school sweetheart, and his adorable 10-year-old daughter.