Too many recent period movies — The Other Boleyn Girl is a notable example — have excessive period detail dumped on them. But writer-director Garth Jennings’s perceptive coming-of-age comedy subtly establishes its 1982 suburban England setting without over-dressing.

In particular, the long tracking that follows Bill Milner’s 10-year-old Will Proudfoot bicycle ride past a street of neat suburban houses and their neat owners, and a cinema auditorium wreathed in smoke, with young Artful Dodger-style reprobate Lee Carter (Will Poulter) happily puffing away, vividly celebrate time and milieu.

Will, coming from a strict religious community, is forbidden television or films, while fellow schoolboy Lee ducks and dives with the best of them.

Unexpectedly but credibly, the odd couple become friends — Lee introduces Will to a bootleg video of Sylvester Stallone’s iconic First Blood and has no trouble in persuading his new pal to be the stuntman hero of his video-camera recreation. Until, that is, French exchange student Dider (Jules Sitruk) enters the picture, straining Will and Lee’s friendship.

It could have all too easily tipped over into schlocky sentimentality. To the considerable credit of Jennings, and the players, it never does, emerging instead as charming, funny and beautifully told.