Christmasissupposedtobeatimeforpeaceandjoyfulfamilyreunions.ButwhenMattandhiswifeKarenshowupunannouncedatthehomeofhisestrangedbrotherStevetocelebratetheholidays,theyareinsteadgreetedwithahorrifyingsurprise:trappedinthebasementisaman.Butnotjustanyman.Stevebelievesthathishostageisnoneotherthanthedevilhimself.