As a child, the future documentary filmmaker had discovered in Boulou, on the Spanish border, in the affairs of his grandparents, an incomplete series of postcards. The maps show the events that took place in his village near the Spanish border in 1939 during the Franco regime. Twenty years later, he sets out in search of twenty-three postcards, deemed untraceable, which are missing from his grandparents' series. And he discovers the story of the Spanish exodus to France.