There’s a King Crimson track, an improvisation called Trio that can be found on Starless and Bible Black, played when the band were knackered towards the end of a European tour in the seventies. Out of nowhere, the band conjure a plaintive melody that seems to sum up exactly where they are at the moment, and which drummer Bill Bruford doesn’t contribute to. There’s no need for him to: what’s there is perfect already. All the same, and rightly, Bruford is credited on the track with ‘admirable restraint’.

In any creative endeavour, what’s not there can be just as important as what actually is. This principle reaches its pinnacle in the sculpture of someone like Henry Moore, say, where the work is defined by negative space, but it also applies in screenwriting.

For instance, Spartan, the thriller written and directed by David Mamet. An excellent movie in so many respects. One of them being Mamet’s typical economy. Like, even though the story is about the kidnapping of the president’s daughter, her identity as such is never once mentioned in the film. We soak up that knowledge as part of the context the characters operate in.

Mamet is similarly economic when it comes to the end of the film, set in the UK. How do we know that? For many directors this would be an opportunity to do a Cool Britannia montage, or at the very least picture someone arriving at Heathrow. Nothing so crass for Mamet. Instead, we become aware of the shift of country because of a scene set in a television showroom, where prices are displayed in-store in pounds. Of course.

This principle of economy, of making the biggest difference through the smallest piece of information seen or heard, is central to effective screenwriting. And it makes the screenwriter’s job one of providing an epistemology for the viewer. Let me explain. Epistemology is about how you know what you know. And the screenwriter’s job is to parcel that valuable information out to the audience gobbet by gobbet, ideally so that by the time the actual story starts, they’re already immersed in the world it depicts. This is done masterfully in Dirty Pretty Things, the superb Stephen Frears directed thriller about refugees and their lives in London.

The first ten minutes or so of Dirty Pretty Things is a masterclass in writing and direction, with information planted through every possible means, directly and through nuance, about the characters’ lives and backgrounds, the world they inhabit, and more. And it also demonstrates the principle of deletion alluded to earlier: what’s not there is just as important as what is. And in the opening section of the film, you won’t see a white face at all. Interesting, and very relevant to the film, which is about a world that the white majority just don’t get to see.

Sexy Beast is, more contentiously, another film I’d say depends on deletion of information for its power. It’s the tale of how Ray Winstone is coaxed from retirement in Spain to do one more underworld job by Ben Kingsley. That, at any rate, is what’s going on in the surface. But every time I’ve viewed it since, I’ve become fascinated by another theory, which is never articulated in the film but explains a hell of a lot to me. We know from the film that Ben Kingsley feels betrayed by Ray Winstone leaving him, bereft of his best friend. Only, I think it goes further: I believe that Ben Kingsley’s character, knowingly or not, is in love with Ray Winstone’s.

Viewed this way, Kingsley’s appalling strops and changes of mood start to make some kind of sense. And I don’t think it’s an accident either: why else would the film be called Sexy Beast, and spend its opening scene with Ray Winstone’s hunk of a man sunning himself by the pool, if there wasn’t some sort of erotic element to the story? Of course, the very notion would appal Ben Kingsley’s character and he’d tear your ears off in protest, but where Sexy Beast is concerned, it’s one of those things that, where once seen, it’s never unseen.