The charming, rousing WWII romance “Their Finest” is a film that openly stumps for two causes: the value of women in the workplace, and the power of cinema to tell stories that people need to hear. Set in London in 1940, the movie stars Gemma Arterton as Catrin, a Welsh writer who moves to the war-torn city to be with her painter boyfriend Ellis (played by Jack Huston), then ends up taking a job writing scenarios for Ministry of Information propaganda shorts. Paid less than her male peers and entrusted mainly to write “the slop”—her co-workers’ term for the female characters’ dialogue—Catrin eventually impresses the head writer Tom (Sam Claflin) when she helps him with a script for a feature-length extravaganza intended to rally the home-front. “Their Finest” is overtly feminist and unashamedly idealistic, but like the project that Catrin and Tom work on together, it mixes its boldfaced messages with some that are more subtle, designed seem into the audience’s subconscious.

Director Lone Scherfig and screenwriter Gaby Chiappe adapted this film from Lissa Evans’ novel “Their Finest Hour and a Half,” which has a title that more accurately describes the text of the story, if less so the subtext. The plot mainly follows the production of one motion picture, backed by an ambitious and sincere continental producer (clearly inspired by Alexander Korda), who thinks he can help win the war with a movie that offers “authenticity informed by optimism.” The Ministry jumps on-board with this plan, pitching a story based on the evacuation of Dunkirk, and more specifically around a news report about two twin sisters who sailed their drunken father’s fishing trawler across the Channel to rescue stranded French and English soldiers. This scenario has everything: working-class gumption, respect for Britain’s allies, and a strong women’s angle.

It’s also, as Catrin quickly finds out, complete hooey. On a research trip, she talks to the sisters and discovers that the newspapers got it wrong, and that they never actually made it more than a few miles from their own shore. But the cynical Tom insists that there’s a big difference between facts and truth, and he encourages Catrin to disregard the former when it gets in the way of the latter. Soon, the Ministry team is inventing a soldier boyfriend and a daring puppy-rescue to make the story more interesting, while also taking notes from their own military higher-ups—who suggest, among other things, that they find a way to work an American into the picture as part of a larger plan to coax the U.S. into the war.

Their Finest Hour and A HalfDirected by Lone SherfigMuch of the fun of “Their Finest” comes from the scenes of the movie being written and filmed. Bill Nighy gives a winning comic performance as an over-the-hill star who keeps beefing up his minor part; and Jake Lacy has a few very funny scenes as the handsome American flyboy who gets hired because he has the right look, even though he’s never acted before. A lot of “Their Finest” has the zippy pace and upbeat spirit of a backstage comedy, with jokes built around the mechanics of the movie business. (One visual gag involving a matte painting is especially sly.) And for a long time, the film has a pleasing predictability too, as it maneuvers the characters so that Catrin will grow disenchanted with Ellis and gravitate to Tom, rom-com style.

But Scherfig and company never let the audience forget that all of this hubbub is taking place during an actual war, and not just on a movie set’s recreation of the frontlines. The production is complicated by air-raids and by the UK’s depleted populace; and nearly all the cast and crew are haunted by the dead bodies they’ve seen in the streets and by the loved ones that they’ve already lost. “Their Finest” even risks its crowd-pleaser status with a rough third-act plot-twist that moves the film away from the simple and saccharine and toward something more thematically and emotionally complex.

“Their Finest” absorbs its shocks well though, because however compromised the Ministry’s film is—by outside input, by commercial concerns, and by a lack of resources—Catrin and Tom keep making sure that every change serves the larger goal of getting Britons to feel better about the sacrifices they’re making for the war. They end up writing something that touches people on a primal level. By the time their picture premieres, there’s nary a dry eye in the theaters where it’s playing—or in the theaters showing “Their Finest.”

Meanwhile, Catrin has her own secondary agenda too: to make sure that her movie’s twin sister heroines aren’t crowded out by the male characters. “Their Finest” can be a little on-the-nose with its progressiveness, having characters comment at length about the rare opportunities that working women were getting in England while their menfolk were off fighting. But Scherfig also reinforces the message in quieter ways, with how she fills the frame. The charity workers on the street corners collecting for war widows? Women. The civil servants keeping people safe from air raids? Women. The post-bombing corpses? Women. There’s a reason why the title of Evans’ novel has been truncated here. “Their Finest” no longer refers to a single 90-minute movie, but to the millions of ladies it aimed to inspire. [A-]

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