When a small group of committed rebels produce a newspaper called Resistance, Lili and her friend The Kid accept the dangerous task of distributing copies of the publication and begin to fall in love.

Lili and The Kid narrowly escape being arrested by the Gestapo and discover there's a traitor in their group. Lili undertakes another dangerous mission, carrying copies of Resistance south to Lyon.

Lili agrees to go undercover to transport a new resistance paper, Combat. Key members of the young communist group are arrested. When the prisoners are tortured, Lili is in danger of being discovered.

Lili joins a new resistance group led by Fredo, a 21-year-old communist, who trains her to use guns, knives and grenades. The Kid is captured by the Germans and sentenced to death by firing squad.

Lili's mission to rescue Victoria from hospital is cut short when Victoria and other leaders of the resistance are captured by the Gestapo. Lili takes a chance to send a coded message to London.

Lili takes drastic action to escape the Gestapo but is later recaptured, along with Jeannot. The Americans are advancing on Paris, but will it be too late for the young resistance fighters?