Eyewitness (1981)

Fresh off the success of Breaking Away (1979), writer Steve Tesich and director Peter Yates re-team on a thriller starring a young William Hurt as a janitor infatuated with television reporter Sigourney Weaver. When she arrives at his building to interview the tenants about a murder that's occurred on the premises, the janitor, having discovered the body, implies that he knows more than he's saying in order to keep the newswoman interested. Although he reveals nothing more, she does become interested in him, and when her nefarious aristocratic boyfriend (Christopher Plummer) learns from the unwitting woman that there's someone with knowledge of the murder, he's more concerned about what Hurt might know than about her relationship with him. Meanwhile, his paranoid, loose cannon of a friend James Woods has managed to get himself incriminated, although he had no involvement in the case. Hurt and Weaver continue to investigate the murder together, and as they become more closely entwined, both of their lives are put in jeopardy.