It's tally ho and chocks away to a tumultuous period when upper lips were jolly stiff and women on the home front actively served the bomb-ravaged nation.
Based on Lissa Evans' novel Their Finest Hour And A Half, Lone Scherfig's wartime comedy drafts frothy drama and heart-tugging romance into active service, assisted by a starry and largely British cast.
Inveterate scene-stealer Bill Nighy delivers another masterclass in deadpan delivery and arched eyebrows as a one-time screen idol, whose glory days are far behind him.
Gemma Arterton is a delightful foil, banging a drum for gender equality in the face of chauvinist condescension, with sterling support from the likes of Richard E Grant, Helen McCrory, Eddie Marsan and Jeremy Irons.
The script, penned by Gaby Chiappe, maintains a brisk pace and a light tone despite the grim historical backdrop, celebrating the power of cinema to dispel the gloom during the Second World War.
"Films: real life with the boring bits cut out," pithily professes one crew member.
Their Finest largely observes these sage words and only permits reality to bite in closing frames when the devastation of the Blitz takes its toll on the key figures.
When her painter husband Ellis (Jack Huston) fails to sell his canvasses, Catrin Cole (Arterton) takes a paid position as a secretary at the British Ministry of Information, which produces propaganda to buoy the nation's spirits.
Roger Swain (Grant) heads up the film division and he entreats scriptwriters Tom Buckley (Sam Claflin) and Raymond Parfitt (Paul Ritter) to unearth a true story of wartime heroism that embodies "authenticity with optimism" and can be immortalised on celluloid.
The real-life rescue of wounded British soldiers from the beaches of Dunkirk by twin sisters using their father's boat is just the ticket.
Catrin is asked to pen the female characters' dialogue - dismissively referred to as "the slop" - and she toils alongside Tom and Raymond to give voice to the sisters.
Before production commences, a pompous cabinet minister (Irons) insists the script should include an American character in order to persuade the United States to join the Allied assault.
Thus, handsome airman Carl Lundbeck (Jake Lacy), who is more wooden than the studio sets, is cast alongside ageing theatrical ham Ambrose Hilliard (Nighy) on a shoot that sparks forbidden romance and mutual respect between Catrin and Tom.
Their Finest is a sweet and charming confection with a full conscription of reliable cliches to keep the cinematic fires burning.
Arterton and Claflin kindle a spiky on-screen romance, conflicted about their feelings for each other until a supporting character observes, "When life is so precious, it seems an awful shame to waste it."
Period detail is solid throughout and director Scherfig makes light work of the two-hour running time.
An exceedingly fine affair.
:: SWEARING :: SEX :: VIOLENCE :: RATING: 7/10
Released: April 21 (UK & Ireland)