This thriller is the second film based on the novel of the same name by Ira Levin. Matt Dillon stars as Jonathan Corliss, a lethal schemer from the wrong side of the tracks. Now a student at the University of Pennsylvania, Jonathan has been obsessed since childhood with the fortunes of a company called Carlsson Copper. Jonathan plans to ingratiate himself with the wealthy family of magnate Thor Carlsson (Max von Sydow) and has begun secretly dating Carlsson's daughter Dorothy (Sean Young). When Dorothy learns that she's pregnant and informs Jonathan that she'll be cut off without her inheritance when her father learns the truth, Jonathan murders her, making it appear to be a suicide, and moves to New York. There, he makes the acquaintance of Ellen Carlsson (also played by Young), the late Dorothy's twin sister, and begins wooing her. This time he meets with success, winning Ellen's hand in marriage and a powerful position in his new father-in-law's company. However, Ellen has long nursed suspicions about her twin's death and as she probes deeper into the alleged suicide, she uncovers alarming facts about some other murders and the identity of her sister's unknown lover. Director James Dearden also wrote Fatal Attraction (1987), which contains similar themes.
by Karl Williams synopsis