The professional wiretapper is in a trial that questions the moral and responsibility of his profession. The mystery unravels slowly, but the threat keeps entailing in a piece of wire. From the elegiac tone of character study type of film, we can see how the terror of surveillance technology blurred the lines of privacy since it first invented. Even for Harry Caul as the outsider, intruding someone else's matter would cost a great expense of paranoia to his internal struggle. Sneaking is necessarily a consequential action.