Composing an iconic theme

As well as the opening scene, the main theme for Jaws is equally iconic.

Composed by John Williams, the two-note melody didn't leave Steven Spielberg impressed, who thought the music maestro was actually pulling his leg due to the simplicity of the music.

The filmmaker recounted: "I expected to hear something kind of weird and melodic, something tonal, but eerie; something of another world, almost like outer space under the water. And what he played me instead, with two fingers on the lower keys, was 'dun dun, dun dun, dun dun.' And at first, I began to laugh. He had a great sense of humor, and I thought he was putting me on."

Williams explained the theme's simplicity was intentional, and told the director it would add more tension to the scene and make it more memorable for audiences.

He said: "You could alter the speed of this ostinato; any kind of alteration, very slow and very fast, very soft and very loud. There were opportunities to advertise the shark with music. There are also opportunities when we don’t have the music and, the audience has a sense of the absence. They sense the absence because they don’t hear the 'dun dun' because you’ve conditioned them to do that."