During World War One, the British troops are entrenched at Passchendaele, Belgium. Among the volunteers there is a young British soldier, Arthur Hamp, who is the sole survivor of his original company. Hamp spent three years in the trenches and this makes him a veteran. He has never been accused of cowardice but one day he simply decides to leave the war behind him and walk all the way home to Britain. In Calais, France, he is challenged by a Military Police patrol who promptly arrests him for leaving without permission. Hamp's commanding officers decide to convene a Court Martial and charge him with desertion. If found guilty, Hamp could be shot by a firing squad. Captain Hargreaves is assigned to be Hamp's defending attorney but he seems skeptical about his chances of acquittal for the deserter. During their first talk, Captain Hargreaves is impressed by his client's utter sincerity and naivete. He learns that his client volunteered on a dare by his friends back home, spent three ...