A paranoid, secretive surveillance expert has a crisis of conscience when he suspects that the couple he is spying on will be murdered.
 
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FUN FACT:  Gene Hackman played a former N.S.A. Agent who is a surveillance expert in Enemy of the State (1998), and the images of his character in his younger days are taken directly from this film. Hackman's characters are so similar in both movies, fans have theorized that they may be the same person, but there is no evidence of this provided by the makers of either film.