A chilling warning scrawled in blood on a neighbour's wall starts an evening of bloody mayhem for the Davison family.

A lively reunion is abruptly brought to an end when a gang of mysterious killers, disguised in animal masks, wage an all-out assault on the Davison's secluded home. Using a series of sophisticated traps, axes, crossbows and machetes, the family are slaughtered one by one until nowhere is safe. But neither the attackers, nor their victims, have counted on Erin; an innocent girlfriend who has the killer instinct to fight back...