1919, Mathilde, 19 years old, learns that her fiancé Manech, who had left for the front two years earlier, has died in battle. A former sergeant tells her that Manech died in the no-man's-land of a trench, but Mathilde is not convinced and refuses to accept what is told. Mathilde therefore embarks on a real counter-investigation. She will slowly unravel the truth about the fate of Manech and his comrades.The path is full of obstacles, but that doesn't deter Mathilde.