Their Finest” is an amusing but affecting drama about ongoing struggle in the face of adversity, through art and also through simple, dogged determination. As London is relentlessly bombed during World War II, the Ministry of Information Film Unit attempts to make a movie that will bolster morale. Its film succeeds, as does this film, in doing just that. Crowds will be pleased by “Their Finest.” It is a poignant, but not (too) cheesy, film.

Movies about movies are a fun genre, and the wartime background gives this story an added element of interest. Gemma Arterton plays Catrin Cole, a smart young lady plucked from the typing pool to assist in adding a female perspective to a film script. Initially, they actually have her write little jokes and dialogue about husbands to entertain female viewers, and the degree to which her efforts are contained within the project are just the first of many great feminist moments. She’s the Rosie the Riveter of screenwriters.

The concept of women rising to the occasion deepens when Mrs. Cole is sent to interview two meek twin sisters said to have undertaken a heroic rescue at Dunkirk. Desperate for money to support her painter husband (Jack Huston), the fledgling screenwriter fudges the drama when necessary to get the project off the ground, and the sisters’ story begins its journey to the big screen.

Richard E. Grant is, as always, wonderful as the government representative, ordering up the dramatic elements required, such as a handsome American thrown into the mix to try to entice the actual Americans to join the war effort. Bill Nighy supplies most of the film’s comedy and a good deal of its heart as well, as a vain, aging movie star, affronted when he is offered a role not as the romantic lead, but as a drunk uncle.

“Their Finest” is adapted from the novel “The Finest Hour and a Half,” which is longer but also makes more sense as a title, and was directed by Lone Scherfig, who directed another marvelously intelligent, deeply literate period film, 2009’s “An Education” with Carey Mulligan and Peter Sarsgaard. This is a more sentimental, less nuanced story, but anchored by a very subtle and delicate performance by Arterton, convincing as a woman still learning her own heart and her own strengths.

And I echo my sentiments from last week as I encounter yet another performance by Sam Claflin, as the gruff head screenwriter grudgingly, then more amorously, working with a female writer. I find him wooden, and his last name is hard to spell. In this film he is once again upstaged by his female costar, which is appropriate to the story, but he could have been more affecting if he had risen to the occasion.

Nevertheless, “Their Finest” is a rather delightful, dare I say inspiring story, and I found myself moved by the ultimate film within the film, too, dabbing away a tear or two just like those terribly beleaguered Londoners in the movie theater. It is also wholesome enough to watch with your parents, and I suggest you do so, for there is no use in attempting to resist the uplifting sentiment of the story, the ingenuity on display and the many worthwhile moments striving to go on living among the ruins of London.

“Their Finest” is currently available to rent.