(L-R) Danny Boyle and Ewan McGregor. Eric Chabonneau/Getty With the release of "T2 Trainspotting" in the US on Friday, we're brought back into the lives of the drug-crazed, down-and-out friends from Edinburgh, Scotland, played by Ewan McGregor, Jonny Lee Miller, Ewen Bremner, and Robert Carlyle. It's 20 years after they embodied the characters in the original Danny Boyle-directed movie that became a cultural phenomenon.

But along with the obvious challenges of creating a worthy sequel to a classic like "Trainspotting," Boyle also had to patch things up with one of his stars.

Boyle, an English filmmaker, cast McGregor, who's Scottish, in his first three movies, "Shallow Grave" (1994), "Trainspotting" (1996), and "A Life Less Ordinary" (1997). But when Boyle released his fourth film, the thriller "The Beach," in 2000, his muse was nowhere to be seen. Instead, Leonardo DiCaprio took the lead of the movie, marking his first major role after becoming an international sensation in "Titanic."

"The Beach." Fox Boyle's snubbing of McGregor led to the two not speaking to each other until 2009.

“I handled it very, very badly, and I’ve apologized to you,” Boyle told McGregor on "The Graham Norton Show" back in January. The director admits that he gave McGregor the impression that he was going to cast him in "The Beach."

"I felt a great shame about it. I was not proud of the way I handled it," Boyle said.

McGregor added: “It’s a big regret of mine that it went on for so very long. It's a shame we didn’t work together all those years. It wasn't about 'The Beach,' it was about our friendship and I felt I was in Danny's first three movies... and then I wasn’t in his fourth and it made me a bit rudderless. I didn't quite get it and, yeah, we didn't speak for a long time, which was a waste.”

The mending of the friendship began when McGregor presented an award, along with a moving speech, to Boyle at 2009's BAFTA Britannia Awards. Now it seems things are very good with the two as they travel the globe promoting "T2 Trainspotting."

They even hinted at possibly working together again soon in a recent interview with Business Insider.

"I would love to do a play with Ewan because he does them now and again. So put in a good word for me," Boyle told Business Insider, while sitting next to McGregor, who laughed.

But Boyle does recall a project he tried to get off the ground while the two weren't talking to each other and thought it would have been perfect for McGregor.

"T2 Trainspotting." Sony "It's called 'Ingenious Pain,' an amazing novel, and it's about a doctor in the early days of surgery," Boyle said. "I tried to adapt it and I was thinking of Ewan for it, but I could never get it — the third act was always terrible."

"And I would have said it was terrible," McGregor added, which made the two laugh.

"Yeah, he would have said, 'It's interesting, but that third act,'" Boyle said.

It certainly seems the two are making up for lost time. But their careers have greatly evolved since they made the first "Trainspotting." McGregor is starring in Disney's live-action remake of "Beauty and the Beast" the same weekend "T2" comes out and will be in the next season of FX's "Fargo" (starting April 19). Meanwhile, Boyle, an Oscar winner, has his own upcoming FX series "Trust." Hopefully the two can find time in their schedules to make magic happen again.