Trainspotting is one of the most iconic films of the last 25 years, a 1996 release that launched a wave of British hits. And it made Ewan McGregor into a star. He had previously worked with director Danny Boyle on Shallow Grave, and they went on to make A Life Less Ordinary together. But their working relationship faltered when Boyle cast Leonardo DiCaprio in The Beach, so McGregor tackled Hollywood instead with the Star Wars prequels and Moulin Rouge.

T2 TrainspottingEwan McGregor stars in 'T2 Trainspotting'

Now the two have mended their relationship and reunited for the 20-years-later sequel T2 Trainspotting, which also features original cast members Jonny Lee Miller, Robert Carlyle, Ewen Bremner and Kelly Macdonald, plus a script by original writer John Hodge.

"It is quite daunting to come back to a character who is so well known and loved," McGregor says. "Like all of the characters in Trainspotting, they are people who we feel like we know. They are like people who we have really met in real life. But I am Renton, and Renton is me."

Watch the trailer for 'T2 Trainspotting' here:


And he says that the story, in which Renton returns to Edinburgh to face the fallout from his betrayal of his friends, resonated with him. "I had these feelings," McGregor says. "I haven't lived in Scotland since I was 17! I moved to London to go to drama school, and I go home every year, because my parents are there, and my brother and his family, and I love it, but I haven't lived there. Of all the characters I've played who've been Scots, Renton is the most Scottish of them all. And I suddenly thought, 'What if I can't do it? What if I'm not Scottish enough anymore?'"

McGregor found reuniting with his former costars helped a lot. "It was really lovely to be back with Jonny," he says. "When Renton is back with Sick Boy, there's something complete about them again. It all came back."

More: Read our review of 'T2 Trainspotting'

And he feels like the film's sense of nostalgia meant just as much to him behind the scenes. "That time has gone," McGregor says of the Cool Brittania heyday of the mid-1990s. "It can never happen again. But it changed our whole existence."

While promoting the film's UK release, McGregor sparked headlines when he pulled out of a planned interview on Good Morning Britain over Piers Morgan's criticism of the 23rd January Womens March. While Morgan launched a flurry of tweets in response, it's telling that McGregor took a more mature response, standing silently by his principles.