Rambo vs. Indiana Jones wouldn't be a fair fight, so what about "Son of Rambow" against Indy?

Reminded his $6 million coming-of-age movie was opening against the fourth Indy juggernaut, writer-director Garth Jennings quipped, "Yes, I feel so sorry for Indiana Jones. They must be terrified. It's going to be difficult for them, but I think they'll be OK."

"Indiana Jones" opened on thousands of screens while "Son of Rambow" might be on seven or eight throughout the country. One of them will be at the Squirrel Hill Theater.

Jennings was on the phone from London, where he was sitting in his front room as his children, ages 5, 3 and 9 months, slept. "That lovely quiet now has descended on the building," he said this week by phone.

He is 35 years old but remembers watching "First Blood," just as the boys in his movie do. "It was the first one I'd ever seen that wasn't meant for my age group, and it was just a mind-blowing film for a 12-year-old boy to be watching."

After all, Sylvester Stallone's John Rambo was a "guy with just a stick and a knife who takes on 200 men. He could sew up his own arm. In that first movie, it was all about surviving and going against 'The Man.' "

Besides, all any boy needed to become Rambo was a tie knotted around his forehead. No pricey costume or laser gun required. And all any boy needed to become a moviemaker was inspiration, provided by "First Blood," dad's new video camera and cooperative friends and family.

Jennings' first movie was "Aaron, Part I," and he says it now seems ludicrous. "I played the head of the Military of Defense who was kidnapped by the PLO and held hostage, and Aaron is my best friend who's also a trained soldier who comes to save me and kill the bad guys."

He drafted his father, who worked for a bank, to play the getaway driver for the terrorists and cast his 9-year-old sister as a feisty news reporter. "We had rolling credits made out of tissue paper and stuff."

Jennings may put his inaugural effort on the eventual DVD of "Son of Rambow" but he quickly explains, "It's terrible. Don't get me wrong, it's not like, oh my goodness, look at the genius. It's the opposite, absolutely ridiculous."

But long before any DVD hits stores, "Son of Rambow" has to finish opening in theaters almost a year and a half after Paramount Vantage bought the movie at the Sundance Film Festival in January 2007. Some licensing issues held up the distribution, but everyone signed off, and Sly saw it and liked it.

It had taken five months for Jennings and producer Nick Goldsmith to find the boys -- neither professional -- to play the leads. "If anyone likes the film, it's because they like those two. I'm just forever in their debt because they're two of the nicest, most lovely people I think I've ever met."

Bill Milner plays Will Proudfoot, a member of a strict religious sect who may preach outside a movie theater but certainly is forbidden from going inside. Will Poulter is Lee Carter, the school bad boy who threatens to smash in Will's face if he doesn't help him with the action epic he's shooting.

Jennings grew up next to a family that belonged to a religious community much like Will's. "It just fascinated me to think that I was living next door to people who couldn't do any of the things I thought, at the time especially, were what life was all about -- pop music, amazing books, movies, just fun stuff.

"None of that was allowed, and I used to think that was extraordinary," he recalled. Why, they had no idea what E.T. looked like.

"Son of Rambow" is set in the early 1980s, and Jennings owes its authenticity to his crew.

"We had this props department obsessed with getting the detail right, absolutely obsessed, to the point where I had to stop them from being so mental." They located 90 percent of what they needed, including such items as authentic candy wrappers, on eBay.

Due to their ages, the boys were allowed only four hours a day on camera but that didn't prove to be a problem.

"We tailored the shoot to them and found ourselves working far more economically than we normally do. I cannot tell you how amazing they were, they kept surprising me. I don't think I ever shot more than three takes on either of them. Invariably, it would be just a single take and they just got it."

Jennings didn't use video playback or monitors on the set, to avoid the time-consuming huddling that occurs and to prevent the children from becoming self-conscious. "They never actually saw a single frame until after Sundance. ... Those things work, keeping it simple but still having all the big toys to play with."

That is what he learned from years of making commercials, music videos for Blur, Fatboy Slim, REM and many others, and directing "The Hitchhiker's Guide to the Galaxy." It's no coincidence that so many moviemakers cut their teeth on music videos, as Jennings and art-school pal and producer Goldsmith did.

"It teaches you to plan meticulously and also you learn how to pitch your crazy ideas to people and actually get them made, and problem solving and not being afraid to do things you don't necessarily have an answer to straight away."

The turnover was lightning quick. "You'd finish something on a Friday and Saturday morning, it'd be on MTV."

Unlike a movie, made in the summer of 2006, snapped up at Sundance in early 2007 and just now arriving in theaters alongside the big boys but with its own comic brand of derring-do.