Son of Rambow

“Son of Rambow” is filled with small surprises and treasures, a veritable bounty of delight. It perfectly captures the innocent, whimsical joys of boyhood, and it does this in the simplest possible way: by being innocent and whimsical itself. When the characters in the movie grow up, I bet they’ll make a film just like this one.

The boys, both about 12 and living in England circa 1983, are as different as can be. Will Proudfoot (Bill Milner) is skinny and timid, obedient to his widowed mother (Jessica Stevenson) and restricted from watching TV or movies by the family’s membership in the no-frills Plymouth Brethren sect. The other lad, Lee Carter (Will Poulter), is a broad-faced bully and mischief-maker. The first time we see him, he’s sitting with his feet up at the local cinema, the only audience member in the non-smoking section, brazenly using a video camera to pirate the film … oh, and smoking, too.

The movie happens to be “First Blood” (often called “Rambo I” nowadays), and Lee Carter has it in his head to make his own Rambo movie and enter it in a young filmmakers contest. He and Will are thrust together by circumstances at school one day, and Lee — an expert con-man as well as a thug — somehow convinces the terrified Will that he owes him something. Lee’s demand is that Will be his stuntman in the film. Will has never seen a movie before, but when he watches the bootlegged “First Blood” at Lee’s house, it instantly becomes the subject of his frequent daydreams.

And why wouldn’t it? All boys, even ones who have been sheltered from mass media, love tales of heroic feats and dangerous adventures. Will’s imagination is his best asset — he draws constantly and has filled an entire notebook with fanciful sketches, and for some reason every day he spits a mouthful of drinking-fountain water into the goldfish bowl outside his classroom. (Why? Because sometimes boys do crazy things that only they understand.) He instantly becomes an enthusiastic participant in Lee Carter’s project — the only participant, in fact, since nobody at school likes Lee. Soon the two are inseparable pals.

Meanwhile, the school is thrown into a tizzy by the arrival of French exchange students, including a super-cool dark-sunglasses type named Didier (Jules Sitruk). All of 14 years old, barely adolescent, and sporting an absurd wisp of a mustache, Didier is considered the very height of awesomeness. He is treated like a rock star. All the boys join his entourage. All the girls line up to take turns kissing him.

Didier’s superstardom eventually intersects with Lee and Will’s film project (conducted in stealth without Will’s mother’s knowledge), which threatens to upset the boys’ new friendship. “Son of Rambow” is ultimately about that delicate balance of childhood relationships, in which the emotions run deep but the kids lack the sophistication to express or understand them. Will and Lee are at the age where everything is in flux, where the kid you used to hate can become your best buddy in a day, and where the social laws that will be strictly enforced in your later teen years — the ones governing who’s allowed to be friends with whom — haven’t been established yet. At this point, even a shy, quiet kid like Will Proudfoot has the potential to be popular, and someone like Didier can use the experience of going to England as an excuse to reinvent himself.

But most of all, “Son of Rambow” is flat-out hilarious — good-naturedly, charmingly, inventively hilarious, with just enough of a subversive streak to give it some zest. Written and directed by Garth Jennings (“Hitchhiker’s Guide to the Galaxy”), it brings Will and Lee’s imagination to life with matter-of-fact special effects (don’t let your impressionable kids see how they do their “stunts”!) and occasional bits of line-drawn animation. It has a grand, Danny Elfman-esque musical score by Joby Talbot and an endlessly creative visual style. Yet even as it’s being funny, the story manages to examine the boys as real, three-dimensional characters: Will’s struggle with his restrictive religion, Lee’s surprising devotion to his mean older brother (Ed Westwick), and the peculiar — but instantly recognizable — dynamic of friendship between the kids.

“Son of Rambow” is for anyone who ever daydreamed about being an action hero, or who had a friend he didn’t understand but loved anyway, or who tried to navigate the perilous waters of adolescence. It’s for anyone who remembers childhood fondly and wants to re-experience some of its magic. In other words, it’s for everyone. This is a thoroughly lovable movie, and I thoroughly love it.

A (1 hr., 35 min.; PG-13, a little vulgarity and reckless behavior.)