A British Battalion moves up ready for the World War One 1917 battle of Arras. A much loved Regimental Sergeant Major is blown up, the man taking his place intensely disliked. A patrol is sent into No Man's Land to rescue a casualty crying for help.

One soldier, a cello player, throws his rifle away when the wrong casualty is shot in frustration. Threatened with Court Martial, he walks alone to find the real one, imagining playing his cello. He finds him, legs impossibly injured, pulls him from the mud and carries him towards a German medical station.

The casualty, Sergeant John Wall, a real soldier shot for desertion in 1917, dies and the cello player is taken prisoner. He runs from the medical station wearing a red cross apron. On returning to his own line he is arrested.

Witness a flawed Court Martial and a bizarre final 'victory' which is to have a profound effect on Ben the cellist's friend and the fundamental question of justice in war.