A chipper tribute to cinema and the scope of youthful imagination, Son of Rambow revisits that chunk of childhood where kids played dress-up, emulated their favorite action heroes and wrought unsung adventures in crayoned cardboard boxes.

In Rambow (a misspelling of the Sly Stallone actioner “Rambo”), two boys in rural England film a bootleg copy of First Blood in theaters, starring everyone’s favorite crossbow-toting jungle warrior.

Will Proudfoot (Bill Milner) is a hyper-artistic yet repressed middle-schooler in 1981 England. Reared in a strictly puritanical religious household, Will’s isolated from devilry like music, movies, novels, TV and newspapers (in one scene, he’s even forced to leave the classroom while a science documentary is screened). Instead, he retreats after dinner to his basement to daydream and draw flipbooks.

This pint-sized pipsqueak teams with school bully and moneyed rebel Lee Carter (Will Poulter), a loner whose deadbeat and absent mom has left him with his equally deadbeat and absent brother. He’s intent on entering the BBC Young Filmmaker’s competition, so this Huck-and-Tom duo of kid auteurs set out on remaking First Blood shot-for-shot. English director Garth Jennings knows how to capture the vivid and carefree moments of dreamy, unashamed randomness from movie-mad youngsters.

The Rambo metaphor works, too: like the muscle-bound forest hero they idolize, these careworn adolescents are ostracized and misunderstood by society and whipped around by authority figures. They’re not about to take AK-47s to their oppressors, of course – just camera lenses.