After the French defeat in the summer of 1940, a young Senegalese infantryman, Addi Ba, flees the army and takes refuge in the Vosges Mountains. Aided by villagers, he manages to obtain false papers that enable him to come out of hiding. He attracts the attention of people who are planning to take action against the occupying forces, who do not yet call themselves members of the "Resistance," and helps them to set up the region's first "underground" network.