At the outbreak of the Spanish Civil War, the nun Maria is forced to flee her convent. She takes refuge in a brothel, until it is liberated by a woman's anarchist group. Maria joins the group and eventually goes to the front. The women's group faces the problems of fighting not only the nationalists, but also factions on the left seeking to impose a more traditional military structure.

Nino, tough but sickly, and his older brother Vicente live in the country with their father. After their father disappears ― we’re never sure why ― murder is suggested. Vicente brings his girlfriend to the house, and a different kind of family is established as the three youngsters grow fiercely protective of each other. But their uncle grows suspicious about the fate of the missing father and forcibly kidnaps Nino, taking him away to the city and leaving Vicente to locate him there.