If you've seen any of British filmmaker Doctor Who" at the start of Peter Capaldi's run.)

His latest film (opening this week) is "Free Fire," and acts as his take on the 1970s American crime thriller. The film is set in a single location (a ramshackle warehouse in Boston), and features a host of colorful underworld types (played by, amongst others, Armie Hammer, Sharlto Copley, Cillian Murphy, and Brie Larson) as they fight, shoot, and curse at each other. It's great fun, in the grungiest way possible, starting out as stately and mannered before descending into hellish depravity. Like all other of Wheatley's films, it's got a nasty subversive streak, too. This movie doesn't glamorize shootouts or gunplay; Wheatley makes sure you feel every bullet.

So it was a real thrill to get to talk to Wheatley about "Free Fire," its unlikely inspiration, and his next film -- a monster mash called "Freakshift" (starring Hammer and Alicia Vikander) that I last spoke to him about way back in 2012.

The last time I talked to you was back in 2012. You didn't mention this project but you always have a long list of things you're going to get to. When did you start thinking about "Free Fire"?

I think "Free Fire" was written after "Sightseers," if I remember. But it had been bubbling around for a long time. And there had been another script that was about close-quarter combat stuff that I'd done which was more of a psychedelic thing. And I think the psychedelic stuff ended up being "Field in England" and there are elements of "Free Fire" in "Field of England" as well, to a degree. But it originally came from reading a transcript of a shootout in Miami that the FBI had done. It was realizing that it was possible for highly trained people to have a close-quarter battle for quite some time and miss quite a lot. And that if you read this transcript it's incredible how messy and chaotic the whole thing is, and how sharply in contrast that is to how Hollywood movies treat this kind of situation. So I thought there'd be a story in there. That was the road to it.You've talked about how it was inspired by movies from the '70s and you even have Martin Scorsese on as an executive producer. Can you talk about what movies you were inspired by and how Scorsese became attached?

"The Friends of Eddie Coyle" was a big one for me, just the coldness and the stripped structure and the harshness of it. But another film that was influential, which wasn't a '70s film, was "Evil Dead 2" (photo above). It became more apparent as we were making it, but that level of swinging the camera around and the slapstick elements of it. We were making it and thinking, This is more [Sam] Raimi than it is the cooler end of '70s stuff. Because it was much more flying cameras and steadicams and techno-cranes and all of those things that weren't likely to appear in a '70s film because they weren't invented. And Scorsese I met through my agent and I knew that he'd liked "Kill List" because he'd done interviews and mentioned it. I thought, Well, I'll use that as my in to see if I can get a meeting. Being such a film fan it's really the pinnacle of fandom to get to chat with Scorsese. So I went and met with him and we spent a couple of hours chatting and it went on from there.

With this movie, you move away from the slicker elements of action filmmaking but still have to keep things in mind, like geography and spatial relationships. Was it hard to juggle the more technical stuff with what you were trying to do with the characters?

Yes. There's a lot of planning that has to go into it. It's mainly practical effects. There's hardly any CG in the whole film. And that's just dangerous and difficult and time-consuming. You make a lot of decisions early on in terms of the setting of the explosives into walls and pillars and all of that stuff. It was all very deliberate in the way that it was made.

Brie Larson told me there was still a degree of improvisation you allowed with the actors. Was that important for you?

The thing is, when they're talking, which is the first third of the film, that stuff is easy to handle. Because they're all on their feet and there's no pyrotechnics and stuff. So that could be a lot looser. It's not improvisation; it's more paraphrasing than it was just letting people make stuff up. It was more you do a take based on the script and you do a take that you can put back into your own words. "No" is not something I say to actors. I want to see what they've got, whatever they've got, and if we've got the time to shoot it, we'll do it. Shutting people down and telling them their ideas are no good is not the recipe for happy performances. You want to have an environment where people are ready and willing to risk stuff.Did you have all of these characters' back-stories worked out, and what all of their relationships were before they end up at the warehouse?

Yeah, totally. But how relevant that is to the film? Not particularly. It's interesting. When I listen to the performers tell me the back-story they've made up for their characters, I just say, "Yeah, OK, I have no idea what you're talking about." But it doesn't matter. It's more about interpersonal relationships of characters in the moment. In a lot of ways, it's about reduction of character not about the expansion of it. It's the fact that you go from being a person with a future who is thinking about their holiday and has their mortgage to pay and is thinking about the girl they want to go out with in one minute and then in the next minute they're crawling around on the ground going, "Am I going to live through the next 30 seconds?" That is not a position where you start remembering things that happened in the past or becoming introspective. You are just reduced to surviving. That's the thing that made me interested in the project. It's kind of what happens in a way situation or even in the current news cycle, where in one minute there's a fact that in the next second means something completely different, and no one can remember how we got here.

One movie we did talk about back in 2012 is "Freakshift." Are you excited about getting Armie involved and finally shooting?

Yeah, man. It's amazing. I'm kind of glad I didn't make it back then, because I've got so much more experience now and I think it would be an overwhelmingly complicated movie to make straight after "Kill List." But it's great that it's finally getting there.

"Free Fire" opens Friday.