A Kiss Before Dying (1991)

Social-climbing Jonathan Corliss romances rich girl Ellen Carlsson in order to get close to her powerful father, but his plans go awry when she becomes pregnant. Feeling cornered, he murders her and moves on to her twin sister, Dory, who proves to be just as vulnerable to his charms. But Dory is suspicious of Ellen's "suicide," and her investigation brings her closer and closer to the shocking truth.