Patriotic German youth Helmuth hears and sees things that make him question his allegiance to the Reich, leading him to secretly write and distribute materials denouncing Hitler and his regime. SS Agent Müssener finds them.

Müssener searches for the leaflet's author. Helmuth increases his production and recruits Karl and Rudi to help distribute them. Hugo discovers Helmuth's radio and forces him out of the house. Elli reads one of the leaflets.

Müssener grapples with a devastating loss. Helmuth, Karl, and Rudi continue their resistance work. Helmuth gains confidence with Elli and asks her on a date. Müssener's investigation brings him closer to Helmuth's identity.

Helmuth is imprisoned and tortured. As he stands trial for treason, he boldly declares the truth. He asks his friends to remember him and he envisions a better world.