THE thing about gunfights, Ben Wheatley tells me, is that they are nothing like the ones you see in TV and movies. “I was reading these police transcripts where police and criminals are blazing away at each other,” he tells me. “It’s not what you expect at all. The reality of it is messy and random and quite chaotic.”

And that is the idea is at the heart of the director’s new film Free Fire, a 1970s warehouse shoot-out movie that indeed suggests that gun battles are messy, random and chaotic. Oh and funny too. In short Wheatley is breaking with tradition. Well, up to a point.

“To say that Free Fire is realistic is probably chancing my arm a little bit,” Wheatley admits. “But it is trying to look at that. Unless you’re hit in the head or in a major organ you tend to have a little time. It is quite hard to shoot something that is moving as well, especially if it’s firing back at you.”

That’s one of the lies the movies tell you, it seems. That everyone is a good shot. “It’s a perishable skill,” suggests Wheatley. “If you don’t practice every day, within two or three weeks you’re no good at it again, apparently. It’s not like riding a bike.

“When you see these news reports where the police have fired hundreds of shots and not hit anybody that’s what that is.”

Free Fire is Wheatley’s sixth film, the follow-up to last year’s JG Ballard adaptation High Rise and another step up the ladder in terms of budget and cast. Not only did he get a proper star in Cillian Murphy on board, he also has an Oscar winner in Brie Larson.

“Yeah. I don’t think Room was even finished when we cast her. I finished the film and then the road to the Oscars happened after the post was done on Free Fire, which was a great bit of luck for us.”

Just as importantly, it gave Wheatley a chance to do something he hasn’t done before, a proper action movie. “I had a chance to do a little bit of action in all the films I’ve done but I’ve never had anything sustained like that. And you can’t do it unless you’ve got a certain amount of budget and a certain amount of control over the environment.”

That has not always been the case. High Rise, he points out, was the first of his films he was able to say what colour the walls should be.

Not that that held him back. Since his debut Down Terrace and its glowering, doomy follow-up Kill List, Wheatley and his writing (and life) partner Amy Jump have become the great white hopes of British genre cinema.

Next up they are hoping to get their long-mooted sci-fi project Freak Shift into production. And then there is the possibility of a remake of Henri-Georges Clouzot’s 1953 thriller Wages of Fear, about men transporting a nitro-glycerine shipment and a film so good it’s already been remade by William Friedkin under the title The Sorcerer in the 1970s. No pressure then.

“When they asked me I thought jeez that’s a really bad idea,” admits Wheatley. “It’s been made twice really very well. But then I thought: ‘You know what? In terms of cineastes, some people have seen those movies. But in terms of the world they haven’t really.

“And also the idea of an old-fashioned adventure that was about tension and pressure and people on a human scale dealing with a very difficult situation that’s what I want to see in the cinema and that’s what I want to direct at the moment. To an audience rocking up to a Vue or a cineplex it makes sense. What’s the review going to be in Sight & Sound? Well, it’s going to be a bit of a tough sell.”

High-Rise is on Film4 at 9pm on Wednesday