"La Ligne bleue," a documentary directed by Marie Dumora, delves into the history of the Struthof concentration camp, the only one ever built on French soil, located in Alsace. The film centers on the villages of the Bruche valley, where the echoes of the camp’s dark past still linger in the memories of the local community. Once a site of Nazi oppression, the area now features a pink granite quarry, which was used to construct German monuments during World War II. Over time, nature has reclaimed the land, and the remnants of the camp are now largely hidden beneath the forest. The documentary opens with a journey along the road built by the prisoners of Struthof, offering a visual and emotional connection to the camp’s history. It explores both the geography and the historical significance of the area, including the path prisoners took to reach the camp in the village of Natzwiller. While the film does not linger on the camp's physical remains—such as barbed wire, the entrance door, and two original barracks—it highlights a reconstructed barracks that now houses a museum. This museum preserves the stories of those who were imprisoned and murdered there. Dumora's film also captures the personal narratives of local residents, many of whom witnessed the deportation of family members during the Nazi annexation of Alsace in 1940. These stories, often overlooked or suppressed, are brought to light through interviews with residents and their descendants. The documentary reveals small but significant acts of resistance, such as villagers slipping food like potatoes to prisoners or a local girl named Edith giving them cigarettes. Some guards, particularly older ones, were known to have shown unexpected kindness, even helping a young local pass letters to their loved ones inside the camp. The film also follows the efforts of descendants who continue to uncover and donate personal items and letters found in inherited homes to the Struthof Memorial. Additionally, young archaeologists have initiated a new excavation project in the pink granite quarry to uncover more evidence of the camp’s history. "La Ligne bleue" underscores the importance of preserving these testimonies, as the memory of World War II and its atrocities continues to fade with time.