So, the homegrown powerhouse duo and pop-promo wunderkinds known as Hammer & Tongs, aka the director Garth Jennings and producer Nick Goldsmith, are back with the movie they always intended to make before their sprawling and only sporadically successful Hitchhiker’s Guide to the Galaxy. Son of Rambow is the story of two chalk-and-cheese pre-teens growing up in an early 1980s suburban England of the imagination.

The awkward, introverted Will (Bill Milner) is a reluctant member of the fundamentalist Christian sect, the Plymouth Brethren, and so pop culture and, specifically, movies are verboten. The abrasive Carter (Lee Poulter) is a latchkey lout who lives in the nursing home run by his absentee parents, is mercilessly bullied by his overbearing brother but harbours film-making ambitions.

Naturally, these opposite misfits are forced together and, after a furtive and inspirational viewing of Sylvester Stallone’s First Blood, the now Rambo-obsessed Will decides to help Carter with his lo-fi production of the titular sequel (misspelt “Rambow” because, like, they’re kids). The effect it has on those around them – including brittle mother Mary (Jessica Stevenson) and the new heart-throb exchange student, Didier (Jules Sitruk) – will be profound.

All this, of course, is very Hammer & Tongs, who delight in the film-making process and in the wildest possibilities of the simplest effects. Thus much of the movie is devoted to naive production mechanics and to a celebratory view of creativity unhampered by resources (the boys use fingers for clapperboard and crayons for bullets). There are beautiful observations in here, about the immersiveness, the everyday cruelty and the casual homoerotica of school life. Occasionally, though, the film-makers’ belief in the wonderment of the process blinds them to dramatic complexities. The ending, in particular, feels as if it has emerged from the pages of a screenwriting manual, rather than out of the reality of their lovingly created characters.

12A, 96mins

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