It's been 21 years since the movie Trainspotting first ran over audiences and into the category of classic films. But despite its success, making a sequel was the last thing director Danny Boyle had in mind.

"There was no inclination on any of our parts to even consider it then, and no one offered, to be honest," Said Boyle recently at the KING 5 studios. "When 20 years loomed on the horizon we were like, we began to think what it would mean to bring them back together again."

In T2 Trainspotting, Boyle brings back the one-time mates who have each gone their separate and sorry ways. Heroin was the bond they shared in the first film, but Boyle says they face something even more ravaging now; the passing of time.

"There's a lot of fun in the film, just like the first film. And some tough stuff as well. But really what it's about is how men age actually. And the truth is, rather badly. We hang on to the past far too long, and the film is partly about that really."

Though the original cast had obviously aged, Boyle was confident they'd come back for another round.

"I knew they would do it. I had no worries of them not approaching it cause to get that kind of range with a character or when a film for all four of them, it’s pretty irresistible."

The only person with trepidation about doing a sequel was perhaps Boyle himself.

"It's horrible having an unsuccessful movie, but if you have an unsuccessful movie and it's a follow-up to a really successful one, you're going to get crucified!"

So while sequels are all too common in Hollywood, Danny Boyle hopes Trainspotting fans will be onboard for his dysfunctional reunion.

"It's a very particular film about a very particular place. But it's honest and I think the new one is honest as well and I think people appreciate that."