Danny Boyle, whose “Slumdog Millionaire” became the little film that could by winning the Oscar as Best Film of 2008, is back with “127 Hours,” a rough but inspiring tale that dramatizes the much-reported experience of Aron Ralston, a rock climber who was trapped in a Utah canyon when a boulder crashed down on his arm and had to sacrifice the limb in order to survive. In a Dallas interview, he discussed the origin of the project.

“It started with the real story,” Boyle explained. “I was in London and I remember hearing the first reports of him being pulled out of the canyon. It was just extraordinary. And I remember waiting a couple of weeks trying to follow the story, and he did a press conference in the hospital. And then I read his book in 2006, and I approached him—I met him while he was on holiday in Europe—about trying to make a film of it. And I described [my concept] as an immersive experience.

“But he wanted to make it as a documentary then, or as a drama documentary, with him being interviewed in sections and other sections dramatized, like ‘Touching the Void,’ which is a wonderful example of that genre. My argument to him was that I didn’t think it would work—I didn’t think you’d be able to tolerate what you have to do without actually living it.

“So we parted company. Then ‘Slumdog’ was a big success, and I think that helped him understand the values I would bring to it as a filmmaker. I also think he changed as a person. He’d met Jessica, his wife, and I think she’d completed his journey properly. I think only then did he finish that journey that had begun in that canyon. Because it was delayed, postponed by the media stardom. He became a big media personality. You become an entertainer. You have to deal with all that, and it postpones the aftershock, the aftermath and how you deal with it. And I think she completed him.

“And he was amazing. Because he gave us actual access to the messages to his family and friends [that he’d recorded while he was trapped], and the freedom to make the film as we wanted to make it. And [star] James [Franco] and I promised that we would literally hand the film back to him at the end, hand the story back to him at the end—which is why…Aron is sitting there, and James kind of gives him back the story. You know, in a year’s time James Franco will be doing, by all accounts, ‘Alien’ prequels—I don’t know what he’ll be doing! And I’ll be doing the Olympic Games [for which Boyle’s scheduled to direct the opening ceremony in London in 2012]. But Aron will still be living that story, and he’ll be picking the moment when he tells [it to] his son. So he’ll always be inside that story. You can only borrow it, respect it and give it back. That’s what we wanted to do.”

How did he choose Franco to play Ralston? “‘Pineapple Express’ is responsible, really. I knew his work as a serious actor, and there’s always this moment when you see someone do comedy that completes him as an actor, I think—the whole arc. I shouldn’t compare him to De Niro, but when De Niro did ‘King of Comedy,’ to be able to go to the comic side as well, is phenomenal, I think. And ultimately we came to rely on those skills, because he can do the whole panorama of moods and tones and contrasts and variations. And obviously it manifests itself in the [scene where he pretends to be] the talk-show host, when he refreshes the film for you—the whole film is suddenly up in the air again, even though he can’t move. And then he stops and leaves this incredibly beautiful message for his mom and dad, saying ‘I haven’t appreciated you in my heart as much as I know I could.’ He’s on a journey, learning all the time.”

But Boyle used all his cinematic skill to give the film a vibrancy and sense of intimacy that would set off Franco’s performance. “It was to make the journey as intense as possible,” he explained. “Because you’ve got no other characters, in effect, James has to play all the parts. He has to play all the tones. So you need a great actor who’s going to have contrast and variation in what he can play. But you also need to provide as much variety as possible as a director. Some of that’s music, and you can do it with rhythm and editing. But you can [also] create worlds, and water is a character in the film. It’s beyond important. You want to give it a point of view, so you put a camera literally inside the water. It becomes something you can almost physically experience.”

The discussion inevitably came to the culminating scene in the canyon, which depicts Ralston actually cutting off his right arm to free himself. “The technique,” Boyle said, “was always based around the idea that the only way you could ever tolerate seeing him cut his arm off is if you have enough empathy with him that you were helping him do it in some way, or at least just thinking, ‘Well, we’ve got to just get through this.’ Otherwise you’re going to leave the cinema, or you’re going to have a horror film for horror film fans, or you’re going to trivialize it, which is an equal danger—that you’re not going to show it. When in fact it took him forty minutes, it involved pain that most men will never get near in their life, and it was a passage, a really important passage, a doorway to something else much greater than itself. And as Aron himself said, ‘I left that canyon a fuller, more complete person’—which is an extraordinary thing to say. So you have to show that scene, and the only way you’ll ever be able to do it is if you’ve created the conditions whereby you’re completely immersed in it and prepared to tolerate it.”

When “127 Hours” screened at the Toronto Film Festival, some viewers actually fainted during the scene. “When it happens, it’s very distressing, because your main concern is the person—that they’re going to be okay,” Boyle said. “I thought about [the scene] very deeply after that. The studio’s reaction obviously was to try and stop the news getting out, because it’s not a horror film. We want this film to be for everyone of a certain age. We don’t it to be just a quartile film, just for young men.

“But when we’d done the scene, and I was aware of this even before we ever started, I followed the book very, very closely in the scene. I haven’t increased it, nor have I decreased it, from what’s in the book and Aron’s experience of it—it’s very close to the way Aron describes it. In fact, if anything that we did, it’s the closest thing to the book. It’s a very faithful film, but that’s the closest thing to the book. It’s tough, you know—people watch bits of it, and not other bits of it. But they get through it, because they want him to get through it, because there’s something on the other side of it that’s greater.

“My biggest worry about the scene is that it becomes the movie—just that scene. [But the movie’s] not about that. It’s a passageway to something else, to something much greater and much more profound and important—which is life being given back again. The idea of this film—that he has to swim back to people, that what connects us all is more powerful than what separates us, is very profound to me. It’s what I believe, absolutely, and part of the process of the film is that you challenge that, your belief, and see if it will stand up.

“It’s a great dynamic for a film. You create incredible odds for a character—in fiction, or in this case, a story which inherently has these odds against him. One of the things I loved about this story is that it was perceived in the media as a superhero story. And for me it was never that. He’s like that before he goes in there—he’s 27, supremely fit, doesn’t need anybody. He’s got everything going for him. Then nature stops him, with a grain of sand effectively, and the journey he has to go on then is to realize that he has undervalued and underappreciated, even hurt the people who love and support him in different ways—that he hasn’t respected them. It’s a very simple journey. But as John Donne said, ‘No man is an island.’ It’s so true.”