This tricky horror flick takes the conventions of the "home invasion thriller" and gives them the self-conscious Scream treatment. The well-to-do Davison family comes under attack during their wedding anniversary when a gang of mysterious masked killers crashes the party. Turns out, however, that one of the guests is a lot tougher than she looks, turning this would-be bloodbath into ... well, a slightly different bloodbath. Look for cameos by indie directors Ti West, Joe Swanberg and Larry Fessenden. 96 minutes R.