Between screenwriting books, film classes and pop culture I knew at least 80% of the film already, but somehow I'd never actually sat down and watched Jaws before. I was surprised how much it reminded me of John Carpenter's (later, 1980) film The Fog, in its scope and mood. Back when horror films were about a monster (puzzle) that a couple of experts had to find a way to conquer (solve). Back when movies were meant to scare you, not just make you jump.
The shark could absolutely pass for real, by the way.