Manchester-born Danny Boyle, in his directing career, has tackled inconvenient corpses (Shallow Grave), heroin addiction (Trainspotting), and the walking dead (28 Days Later). Now, with his new film Millions, he's taking on a challenege even more daunting: children.

Written by Frank Cottrell Boyce, Millions focuses on 9-year-old Anthony and 7-year-old Damian, two brothers in northern England. Their mother has recently died, and their father has moved them to a shiny new suburban development, so that they may all begin again. One day, young Damian - a dreamer fascinated by saints and miracles - finds a suitcase full of money. He tells only his brother and the two boys find their lives are quickly changed by the secret, as they learn the worth of their treasure and find peace with the memory of their mother.

"I think the film's about saying goodbye, and how important that is," said Boyle, in Seattle last month. "At the end of the film, it confirms (Alex's) world view, which is that unreal things are more important than real things, you can keep what you've got by giving it all away. Whereas the real things that his brother is obsessed with are undermined."

Relaxed and excited as he chatted about the film, Boyle had nothing but praise for his two young stars, found after a massive search (what casting directors call "kissing frogs," he said). Lewis McGibbon, who played Anthony, was 11; Alex Etel, who played Damian, was just 7 when he was cast.

"There was a serious difference between them, just like there is in the film," Boyle said. "The 11-year-old was already stained with adulthood, just like the character. Whereas Alex was not. Somewhere between 8 and 10, 8 and 11, they change - that foot gets dipped in the other world, and from then on, they're yearning to get there, to learn all the tricks of adulthood. But (Alex) had no interest in that world at all."

McGibbon had done a small amount of TV; while the angelic-looking Etel had never acted. But Boyle was struck by him, as soon as he entered the room. "He's just got that kind of face you can get lost in. You have to have that in the cinema. You've got to kind of lose yourself in them. In movies, their faces are 40-feet high. There's got to be something tangible there that you can't quite put your finger on, you want to know more about him or you want to share his experiences."

Teaching the boys to act for the camera, Boyle said, was a task that required tossing aside much that he knew about working with adult actors. With kids, he said, "you tell them to do things in certain ways and you watch them and it's just fake, it's really shallow. With a lot of kids in movies, you can see that sense of being told to say that line - you just cringe. Adult actors, they accept that they're faking it. But with a kid, you think, this is their innocence and naivete. You have to jettison everything," Boyle remarked, with a grin, that he enjoyed the experience very much, "because I like larking around, like a kid, messing about."

Not every experience on the film was a lark; at some points, things got very serious, as the boys had to cope with a story like that involved a dead parent. "It's very difficult, because most kids have no experience of death, if they're lucky," said Boyle, who found the children's mothers - who were on the set every day - to be helpful. Alex's mother, in particular, was able to translate Boyle's thoughts for her son at a level that he could understand. "She knew his life experience, she could say, 'it's like when your guinea pig died,' things like that. That helped a lot."

Millions was miles away from the grim subject matter of 28 Days Later, but Boyle's happy to have the change. The movie business tends to pigeonhole - if you've made a successful romantic comedy, for example, the next 10 projects you'll be offered will be romantic comedies - but Boyle has successfully seesawed among genres.

"It's a really good idea if you can do that, to make a big switch like that," he said. "It feels like you're starting again on something, just starting your career off again."

28 Days Later was a huge hit, in Britain and elsewhere, and plans for a sequel, 28 Weeks Later, are under way, though Boyle says he will have little involvement other than reading the screenplay. He's now preparing to cast his next film, a science-fiction adventure called Sunshine, about a mission to the sun.

But clearly Millions, which bears a dedication to his parents ("just a gesture of love toward them"), is close to his heart. He spoke of Damian's fascination with the lives of saints, and of his own Catholic-childhood encounters with those stories.

"A huge light shines on these people, that's why they're saints," he said, remembering the books he once read about those vivid lives." That's why people are fascinated by them. Movies are just the same, aren't they? Shine a light on these people, and entrance people with storytelling."

© 2005, The Seattle Times. Distributed by Knight Ridder/Tribune Information Services.

Millions is currently playing in theatres.