The mockumentary has become a well-worn comic device, and this low-budget British feature, shot in five days without a script, could easily have fallen horribly flat. Its leading character is a down-at-heel roadie called Nicholas, inexplicably rechristened Le Donk, who leads a shabby suburban life much like Steve Coogan’s sitcom character Saxondale. The director is Shane Meadows, a still-maturing talent whose serious work is often better than his funny stuff, and whose bittersweet touches can easily be eclipsed by the Y-fronts, wigs and Pot Noodle gags that he adds for light relief.

Le Donk, though, is a success, a familiar but very funny film-within-a-film in which Paddy Considine, as Le Donk, proves what a wonderful actor and gifted comedian he is. Although Le Donk’s world is music, Meadows’s faux documentary is thankfully light on in-jokes; the title character could as easily be a plumber or an electrician. At a brisk 71 minutes, the film, which had its premiere last night, simply flies by.

This also might be Meadows’s most commercial film to date, making some lovely observations about fatherhood as Le Donk awaits the birth of his first child. Separated from the mother (Olivia Colman) and jealous of her relationship with her new boyfriend, Le Donk starts out as deluded loser but reveals himself to be a kind, even generous man with a surprising sense of humility.

Many of the laughs stem from Le Donk’s child-like glee at being the star of his own movie. But there is a nice sub-plot about Le Donk’s protégé, the real-life Nottingham rap artist Scor-zay-zee. The moon-faced, semi-coherent white rapper is both in on the joke and the butt of it, with Meadows making the most of Scor-zay-zee’s gormless, thriftstore B-boy appearance. But there is warmth here too, and a scene in which the rapper opens for “The Arctical Monkeys” (as Le Donk insists on calling them) is a surreal triumph.

The only real flaws in the film are its two musical montage scenes, with the kind of romantic indie acoustic rock that crops up regularly in Meadows’s films. It is frustrating to see Considine’s lips moving and wonder what is being drowned out. His capacity to hold both the character and the camera is truly exceptional, and it is telling that the film loses impetus only when the director drowns him out.

These, however, are quibbles about a lovely, engaging human comedy. When Considine and Meadows (who first worked together ten years ago on A Room for Romeo Brass) are on top form, there really is nothing to do but sit back and enjoy it.

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