Blow Out (1981)

While in post-production on a low-budget slasher film, Philadelphia sound technician Jack Terry is told by his producer that he needs a more realistic-sounding scream and better wind effects. While recording potential sound effects at a local park, he sees a car careen off the road and plunge into a nearby creek. The male driver is killed, but Jack manages to rescue a young woman named Sally Bedina and accompanies her to a hospital. There, a detective interviews Jack about the accident, and Jack asks Sally out for a drink. He learns that Governor George McRyan was driving the car and that Sally was his escort. Associates of McRyan attempt to conceal Sally’s involvement, and persuade Jack to smuggle her out of the hospital.

Jack listens to the audio tape he recorded of the accident, wherein he distinctly hears a gunshot just before the tire blow-out that caused the accident, becoming suspicious that the accident was actually an assassination. He learns from a news report that, seemingly coincidentally, Manny Karp was also in the park that night and filmed the accident with a motion picture camera.