★★★★☆

Danish director Lone Scherfig’s film about filmmaking opts for a similar spirit of stiff upper-lipped positivity. It’s full of the keep calm and carry on attitude which characterised the era, where people firmly believe that a cup of tea can solve all. “Film is real life with the boring bits cut out,” says Sam Claifin’s wearying scriptwriter Tom Buckley with tongue firmly in cheek shortly after a young Welsh lady, Catrin Cole (Gemma Arterton, perfect in her role) joins their midst. Engaged primarily to write the “slop” – a somewhat degrading term for female dialogue – Catrin soon shows she has far more to offer. She, together with a terrific supporting turn by Rachael Stirling, is a resolute cat among stuffy pigeons who baulk at the notion of women with ideas above their station.

Just as gender politics, targeted use of choice vocabulary and the construct of dialogue is crucial to the success of the play within this play which tells of one miraculous Dunkirk rescue, the script of Their Finest – adapted by Gaby Chiappe from a novel by Lissa Evans – bounces along nicely with more than a nudge and a wink to the vagaries of bureaucracy and the cinematic process which feel just as relevant now. “I know only my art,” says Bill Nighy’s scene-stealing ageing thespian Ambrose Hilliard. Never has the utterance of “semolina pudding” ever dripped with so much vigorous yearning and a cocked eyebrow here and there along with his wonderfully dry self-assurance make this one of the British actor’s finest, most uproarious turns in years. Richard E. Grant, with a cameo as Whitehall man Roger Swain, says more with a sideways glance and slight rolling of the eyes than most could with pages of dialogue; Jeremy Irons is his gruff, commanding self as another higher up the food chain; Eddie Marsan is amusing in a buffoonish way as Hilliard’s agent; and Henry Goodman as Hungarian studio head Gabriel Baker is another cast addition.

The relationship that develops between Catrin and Tom, in spite of her marriage to a struggling artist (Jack Huston), is handled with a restrained warmth which avoids any over-sentimentality, the two actors playing the caustic, frustrated friction of circumstance well. All onscreen are very concerned with making a worthwhile picture, a project to make a difference to the war effort and people in dire need of hope. Their Finest by no means reinvents the wheel but in the hands of Scherfig – who previously directed An Education – it looks wonderful, has enough substance to back up its gleaming charm and is a very enjoyable period piece that wears its heart and intentions firmly on its well starched sleeve.