In Ramsden, a small Yorkshire town, a devoted choir faces a turning point when their choirmaster leaves for the army and the group considers appointing Dr Henry Guthrie as his replacement, despite Guthrie’s sexuality, Germanophilia, and atheism. A brick crashes through the audition room window, bearing a taunt that reads “Hun muck,” directed at Guthrie and the idea of performing Bach’s St Matthew Passion. In response, Guthrie proposes Elgar's The Dream of Gerontius, a choice that is accepted even as some worry about the composer’s Catholicism and the work’s inclusion of purgatory. To counteract a thinning male chorus, Guthrie brings in male voices from the nearby military hospital, expanding the group’s reach and its sense of purpose.
Two of the singers begin a romance, as Bella plays Bella, and her sweetheart Clyde—the young man she cares for—has become missing believed dead. Clyde eventually returns, arriving back in Ramsden with his arm amputated, a moment that tests Bella’s commitment and reshapes the group’s dynamic. At the same time, Guthrie receives devastating news: the German battleship Pommern has sunk, a blow intensified by the parallel surge of support from Elgar for the new plan. Guthrie is overwhelmed with grief, haunted by the memory that his lover was a sailor on that very vessel.
In another thread, Guthrie’s gay pianist Robert Emms confides his intention to register as a conscientious objector rather than face conscription, a stance he attempts to justify before the board, though the effort ultimately does not sway them. The group’s limited resources force practical changes: Duxbury yields the lead role to the talented Clyde, and the production is reimagined as a semi-stage piece, with Gerontius recast as a wounded soldier and the Angel reimagined as a nurse. The revised plan moves forward, but when Duxbury mentions the changes, Elgar withdraws his permission, casting a fresh shadow over the project.
Undeterred, the choir decides to present the performance for free, and the night becomes a remarkable success, drawing notice from the town and beyond. Soon after, three of the men are conscripted, with a fourth spared due to epilepsy, but the pressures of war press in on them all. On the eve of their departure, one member seeks to lose his virginity with a sex worker, while another visits his girlfriend Mary, who will not have sex because of a deal she has made with God for his safe return. Meanwhile, Robert Emms is taken away by Military Police, and the three conscripts board a train in uniform, their faces reflecting a mix of resolve and unease as they say goodbye to their sweethearts and families, already where memory and duty begin to blur.
