During the Great War in an Austrian trenches on the Italian front we follow the adventures of some soldiers. It's a lull between a battle and another and between the two fronts has set an implicit and fragile agreement on non-aggression. During a survey the Austrians find in a ruin an old piano and take it into the trench. A former concert pianist begins to play and the music makes the soldiers forget the distance between the two sides, creating a strange feeling of brotherhood. always undermined by a possible rupture of balance.