Movies based on famous novels usually don't change the title or the characters' names, even when a finished film bears little resemblance to its source.
Mark Steven Johnson, a longtime fan of John Irving's novels, felt that wouldn't be fair when he decided to adapt Irving's 1989 best seller, "A Prayer for Owen Meany." He knew he'd have to make major changes, and he asked Irving to help."The novel just knocked me out," Johnson said during an interview. "I was reading it and seeing the movie (in my head), which I knew would have to be different. Instead of this, I wanted to do that. I knew, for instance, that I could never write about the Vietnam War."
The war is an important part of the novel, and it's not in the movie at all. Neither is the adult friendship of the two central characters. Only their childhood is dramatized in "Simon Birch," which became the film's final title after "A Small Miracle" was considered, then dropped. (The film opens in Salt Lake theaters Friday.)
"The book follows them through their whole lives, and they go off to war," Johnson said. "It's interesting stuff, but I couldn't think of a way to do it. Sixty (percent) to 70 percent of the book is still there."
He admits that Irving was taken aback when Johnson told him about his plans.
"He said, `My book is about two things: religion and Vietnam. And you want to take out Vietnam.' But I thought Vietnam had been done to death in the movies, and I couldn't think of a different approach."
Because he was "afraid I'd have all the `Owen Meany' fans coming at me at dinner parties with knives," Johnson and Irving worked together on changing the title and the characters' names.
"He became my partner in it, and he's a huge supporter of the movie," said Johnson. He disagrees with Entertainment Weekly's fall-preview issue, which claims that Irving is "distancing himself from the project."
"That makes it sound like he's estranged from the film and took his name off it, but that's not true." Indeed, the credits still read: "suggested by the novel, `A Prayer for Owen Meany,' by John Irving."
Simon Birch, played by newcomer Ian Michael Smith, is the tiniest child ever delivered in the history of his small town's hospital. Nevertheless, he has more confidence in his destiny than any of the other kids, including his best friend, Joe Wenteworth (Joseph Mazzello).
Casting the part wasn't easy. At one point, Johnson found himself at the Little People Association Convention, attended by 1,500 dwarfs.
"It was very strange. Everyone was looking at me because I was the outsider."
Smith was the first person he looked at for the role, and eventually he decided no one else came close to Simon.
"I saw hundreds of kids, and the more I saw the more I realized Ian was the one," he said. "He's not Disney-like cute. He's beautiful, he just breaks my heart, but he also makes me laugh. He's a prickly little guy in the movie. I didn't want to ask for too much sympathy."
For a while, it looked like Johnson might be competing for Smith's services with another movie: "Ian went up for Kieran Culkin's role in `The Mighty.' We lucked out: Kieran got the part."
Johnson was initially reluctant to cast Mazzello because he hadn't been impressed with his work in "Jurassic Park."
"But he's an incredible actor," he said. "I did 16 different shots of him in a crying scene, and he cried on every one of them. Oliver (Platt) was watching and he said, `I can't do what that kid does. He's a ge-nius.' "
Sandra Bullock was originally signed to play Joe's mother, but Ashley Judd took over when Bullock dropped out two weeks before shooting started.
"She was committed to the movie, but I had a feeling that it wasn't going to happen," said Johnson. "I still don't know what happened."
The biggest name in connection with "Simon Birch" is Jim Carrey, who narrates the film and briefly plays the adult Joe.
"I knew it would help to have a big star to narrate the movie," said Johnson, who was at first certain that Carrey's asking price would be out of his range.
"Jim's getting $25 million per movie, and this film only cost $18 million. I didn't know him, but he wanted to be a part of it after he read the script. We had just one day to shoot his scenes and do the narration.
"I'd seen him in (the dramatic film) `Doing Time on Maple Drive' on TV, so I knew he had the (acting) chops after that. This can be an emotionally punishing story, and I wanted to have his voice along the way to lift your spirits. I wanted to do anything to prevent this from becoming an art-house movie."
Johnson spent some time with Carrey and realized how difficult it is for him to have any privacy. They were followed everywhere by photographers: "No wonder he committed to `The Truman Show.' That's his story. He is in a fish bowl."
Johnson, who is 33, is making his directing debut with "Simon Birch." A Minnesota native, he was 26 when he sold his first script, "Grumpy Old Men," to the movies.
Ordinarily, young screenwriters have more of an uphill battle to become directors, but because of the success of "Grumpy Old Men" and its sequel, which he also wrote, he was able to persuade Disney to back it. It helped that he'd spent a lot of time on the set during the location filming of "Grumpy Old Men."
"They wanted me as a consultant in Minnesota, and to rewrite lines when Walter (Matthau) didn't want to say something," he said. "I also got to direct the second unit a lot. So it was not a big shock to be di-rect-ing.
"That said, there's a lot to be said for writing; you can write when you want to write, in your underwear if you like. When you're directing, you have to get up at 6 a.m. and everyone wants you to tell them what to do. It's all about management. You have to make a thousand decisions.
"Everyone's saying `is this OK?' and if it's not then you have to do a little Psych 101. If you've told the costume designer you don't like the dress, and she starts crying, then you have to do some com-forting."
He said he's been offered a lot of scripts since finishing "Simon Birch" but can't imagine directing something he didn't write.
"I'm more of a homebody," he said. "I'm really a reluctant director. It think the job's overrated."
As a writer, Johnson has one more movie due this fall: "Jack Frost," starring Michael Keaton as a musician on the verge of making it big, who dies in a holiday highway accident. He comes back in the form of a snowman built by his son, Charlie.
"I wrote the original script, but it was rewritten, the director (Sam Raimi) dropped out and then so did George Clooney," said Johnson. "I'm afraid to see it but I hope it's good. I think it's going to be more of a kids' movie than I in-tend-ed."