Trainspotting, the breakout British hit about drug addiction in Edinburgh that made instant stars of Ewan McGregor, Johnny Lee Miller and Robert Carlyle – and set director Danny Boyle on an Oscar-winning trajectory – will celebrate its 20th anniversary next year. Should everything go according to plan, 2016 could be the year that the much-discussed sequel hits cinemas after shooting earlier in the year.

Speaking to The Hollywood Reporter while promoting his latest film Steve Jobs in London, Boyle confirmed that the shoot was planned for “May/June,” but due to Miller and Carlisle’s U.S. TV commitments (they star in CBS’s Elementary and ABC’s Once Upon A Time, respectively), it might well be as tight as the first, which was filmed in just seven weeks.

“They only get this little window off, so either you wait for the contract to run down, which could be as late as three years, or you kind of try and do it in this window,” he said. “But all four lads [McGregor, Miller, Carlisle and Ewen Bremner] are back in.”

The plan is then to release the film as early as next year.

While the original was made on a shoestring budget of just $2 million, the sequel is set to cost much more, but Boyle says it’s low enough to keep away any meddling hands.

“We’re doing it for less than $20 million, and that’ll give us control of the film so we can make the film we want to make,” he said. “That’s as much as you can get without being answerable to anybody. You can sort of get on with it without much interference. Although we could have raised a lot more money for this, we didn’t so we’re trying to keep some sense like we kept the original.”

Boyle also confirmed that he had a “big business meeting” with U.K. broadcaster Channel 4's production arm Film4 – who helped produce the first – lined up, and hoped they would be on board.

Staying true to the original has been one of the main concerns for the sequel, talk of which has been raging for years. McGregor initially said he wasn’t interested (he famously fell out with Boyle for casting Leonardo DiCaprio in The Beach, although the two have since made up) and Boyle himself admitted there were reservations among the cast.

“The actors were understandably worried about its reputation and not wanting to let people down or to just be cashing in,” he said. “So actually the script, which John [Hodge], has written has been put under a very fierce spotlight by everyone, and it’s a good one.”

While the sequel will borrow elements from writer Irvine Welsh’s Trainspotting follow-up Porno, set 10 years after the original, Boyle said Hodge’s script for the film is “it’s own thing” and not like the book.

“Everyone’s attitude is that it’ll be an honorable addition and an interesting addition to the original film. We’re very positive that we believe it can happen and it’s coming true.”

It's official: Danny Boyle is shooting Trainspotting 2 next summer, with Ewan McGregor (Rent Boy), Jonny Lee Miller (Sick Boy), Ewan Bremner (Spud) and Robert Carlyle (Begbie) all reprising their roles from the classic 1996 film. Trainspotting screenwriter John Hodge has scripted the sequel too, and though Boyle has said it's only "very loosely based" on Irvine Welsh's own follow-up novel, Porno, we don't know much else. So when NME spoke to Carlyle on the phone earlier this week, we had to ask if he'd tell us any more.

How are you feeling about shooting Trainspotting 2 next year?

"It's nerve-wracking to a certain extent, because I'm obviously aware of just how much people loved the original film. People still quote lines to me on a fucking daily basis. I get it everywhere; I can't fucking escape it! But I'm grateful for it too - Begbie has been fucking terrific for me and my career. So therefore - and I think probably if you asked the rest of the boys, they'd feel the same - I'm slightly wary about it all."

Have you read the script yet?

"Yeah, we've already had a read-through of the script, we did that in the springtime. You're going to think, 'Of course he’s going to say this,' but honestly, it's one of the best scripts I've fucking read. I mean, ever. What John Hodge has done is just so clever."

Clever in what way?

"Well, obviously these four characters are 20 years older now and I've never seen a sequel that takes place 20 years after the original, so I think that gives it a certain unique quality. And of course, the audience is 20 years older too - people who came to see the original film when they were in their early twenties are very different people now. And the way John Hodge has put this thing down, obviously with the help of Danny Boyle, is to make it about how the characters' lives have moved on… or have they? Without giving anything away, maybe some of them haven't really moved on. That's what the audience is going to have to go through with them. I tell you, this film is going to be quite emotional for people. Because the film sort of tells you to think about yourself. You are going to be thinking: 'Fuck. What have I done with my life?'"

So it's going to make us question ourselves?

"Yeah, that's really what the whole thing is about. Have these four characters changed? Have they remained the same? Have they fucked it up completely? Have they achieved anything? And of course the audience are going to be asking themselves exactly the same questions. So it's a beautiful thing, this film. And though I'm obviously feeling a little bit tense about it because of the success of the first film, I'll tell you this: if anyone can pull it off it's Danny Boyle. He's the best director I've ever worked with, he's immense."