Bad Influence 1990
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Directed by Curtis Hanson | Starring: Rob Lowe, Marcia Cross, James Spader, Lisa Zane
Wimpy young executive Michael is about to get pulverized by a jealous boyfriend in a bar when a handsome, mysterious stranger steps in—and then disappears. Later that night, Michael runs into a stranger on a pier, who wheedles his way into Michael's life and turns it upside down.