In 1971 this kid Steve Spielberg has a neat idea for a movie. What about a fight to the death between an unstoppable monster that no one believes is real, and an overmatched and unprepared protagonist?
In 1971 that TV movie was "Duel". Then in 1975 that wide-release movie was "Jaws". Check out the similarities...
Youtube says "Duel is a 1971 television (and later full-length theatrical) thriller film directed by Steven Spielberg and written by Richard Matheson, based on Matheson's short story of the same name."
Enjoy...