While observing neighborhood Christmas lights, the Harris family witnesses the death of a young couple at the hands of a supernatural creature. Stricken with shock, the family must come to terms with leaving a couple to bleed out on the country road. The psychological struggle becomes over-bearing on Mrs. Harris as she suffers from post-traumatic stress, which impacts her job and well-being. Overtime, her body begins to shut down with guilt of the attack. Her young son slips in school, trying to cope with the existence of a supernatural creature. Meanwhile, Mr. Harris watches his family fall apart, unable to gain control, ultimately resulting in his wife’s suicide. Now alone, he reconnects with his son by bonding over the possibility of a creature’s existence. Playing detective, Mr. Harris soon discovers a gap between his sanity and reality as he questions what he saw that night. Together, the father and son begin an assault to kill the beast that destroyed their family.