Ayoungnewlywedcouplefindthemselvestrappedinanetworkofundergroundcaves.Withherhusbandinjured,thenewbrideisforcedtofindherwaybacktothesurfaceinordertosavehislife.Intheprocess,theydiscoveraterrifyingtruthabouttheunderneath,theyarenotalone.Somethingevilishuntingthem.