Trainspotting, Danny Boyle’s classic 1996 film about the exploits of heroin addicts in Edinburgh, based on the novel by the provocative writer Irvine Welsh, is getting the sequel treatment. Welsh published his own sequel, Porno, in 2002, which saw some returning characters move into the adult film business, and now Boyle’s getting in on the act (as in, he’s making a sequel, not mucky movies, as far as we know). There aren’t a massive amount of facts for fans to feast on just yet, but in case you want to get up to speed… here’s everything we know so far.

It’s shooting soon

That is, May and June this year.

Because it’s now or never

Well, it’s now or about “three years’” time. Speaking to The Hollywood Reporter, Boyle explained that Robert Carlyle and Jonny Lee Miller would only have a short amount of time away from their respective TV shows Once Upon A Time and Elementary. “They only get this little window off,” he said, “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. But all four lads are back in.”

Ewan McGregor has changed his mind

Reports of the project have noted that the actor, who played the loveable anti-hero Renton in Trainspotting, had previously said it would be “a terrible shame” to make a sequel. Actually, that’s not quite accurate – in 2003, at the Cannes Film Festival, he said: “It would be a terrible shame to make a sequel if it wasn’t as good,” which isn’t quite the same thing, is it? (Although he also went on to say he didn’t enjoy Porno as much as its predecessor, which is a bit awks).

The four main cast members will return

Along with McGregor, who’s had over 10 years to change his mind, the three other main cast members – Carlyle (aka violent psychopath Begbie), Ewen Bremner (simple, sweet Spud) and Jonny Lee Miller (the debonair Sickboy) – will reprise their roles.

It’s only “loosely” based on Porno

Which Ewan McGregor may be pleased to hear. The project was first announced in 2013, when Boyle explained at SXSW Film Festival in Austin, Texas that it wouldn’t be an overly faithful adaptation of Irvine Welsh’s follow-up novel.

The budget is bigger

Trainspotting was made for around £1.5m but this one could be closer to around £13m, though Boyle wants to keep it below that to minimise studio interference.

It won’t be called Porno

Because you can’t Google that at work.

The original scriptwriter is back

John Hodges, who penned the BAFTA-winning Trainspotting script, has apparently already rattled off the as-yet untitled screenplay for the upcoming sequel. Boyle has already been bigging it up as “terrific”. No pressure, John.

The script is finished – and it sounds pretty great

That’s according to Robert Carlyle (Begbie) who we spoke to last year. “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.”

The film is going to make us all get a bit introspective

“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?'” Robert Carlyle told us last year.

It’s coming very soon

The film is expected in 2016, 20 years after the original. And we can’t wait.