Gemma Arterton plays Catrin Cole, a newly appointed script writer working on wartime propaganda films in the middle of London in the Blitz. The Ministry of Information wants a film that the public will relate to, so when Catrin finds a tale of two sisters who took part in the Dunkirk evacuation they jump on it as a possible storyline. Working with fellow writer Tom Buckley (Sam Claflin) and over-the-hill actor Ambrose Hilliard (Bill Nighy) they gradually pull it all together, though not everything goes their way. Catrin faces many challenges, personal and professional but succeeds. The overall tome of the movie is sweet.