 SPOILER: The original ending had Karen and Elaine fighting each  other with a knife when Karen manages to trip Elaine and she tumbles  down the stairs and breaks her neck in the fall. Although part of  this ending had been shot, director James McDonald (IV) (qv)  decided instead, to go with an alternate ending where Elaine ends up  poisoning Karen and waits for Steven to come home, knife at the  ready.