简介：　　Acoupleonthevergeofanastydivorceattempttoselltheiremptylovenestandmoveonwiththeirlives,separately.Afterasuccessfulopenhousetheyarehorrifiedtodiscover,dayslater,thatapotentialbuyerdidn'tleavetheirhome.WhileAliceisbeingheldcaptiveintheba<x>sement,theunannouncedhouseguestmovesinupstairs.Shesenseshercaptureisbeingkepta...…