Brad and Abby Cairn (Sam Rockwell and Vera Farmiga) seem to haveit all: a happy marriage, a spacious Manhattan apartment, agifted nine-year-old son and a new arrival on the way. But youngJoshuas resentment toward his baby sister triggers a series oftragic events that fill the Cairn household with utter despairand unspeakable horror. Is it all a series of eeriecoincidences...or the calculated agenda of a sinister siblingwith the perfect plan for revenge?