After she has a nervous breakdown, a wife and her husband move into a new house. However, she begins to suspect that that her husband and his sister, who is visiting, are up to something ...
Greg Sanderson is helping his wife, Jan, to recover from a nervous breakdown and revive their strained marriage. Their privacy is interrupted by the arrival of Greg's stunning and mysterious sister, Laura. Jan's paranoia deepens as she suspects that Greg's and her sister's relationship is too close. In her desperation, she confides her fears to the landlord but his weird reaction only creates more confusion.