Absorbed by his love, Marius has been unaware of the deteriorating political situation. Now his private crisis is echoed by the crisis of an imminent insurrection. His friend Enjolras directs the erection of a barricade in front of the Corinth wine shop. The first enemy he has to deal with is found within the rebels' ranks. It is Javert, who is unmasked as a spy and tied up to await execution.
Marius, driven by despair, decides to seek death in the insurrection. He joins the fighters at the barricade and fights valiantly to the end. Valjean also joins the insurgents, but for special reasons. He has discovered Marius' relationship with Cosette and his role in the revolution. For Cosette's sake, he decides to protect the life of the man he abhors.
Before the final assault, Valjean volunteers to execute Javert. Instead, he spares the inspector's life and sends him away. Then Valjean returns to the barricade as the few surviving defenders are driven inside the wine shop. He seizes the seriously wounded Marius, disappears into a manhole, and undertakes a heroic and harrowing passage through the sewers of Paris. Unfortunately, Javert arrests him at the exit. However, he allows Valjean to take Marius to his grandfather and later, in a quandary, releases Valjean. But he cannot forgive himself for this breach of duty and commits suicide.
Marius' life has a happier ending. He recuperates from his wounds and overcomes his grandfather's hostility to his marriage. The marriage, however, is a mortal blow to Valjean. He has confessed his past to Marius, and the latter, in spite of his magnanimity, slowly estranges Cosette from Valjean. Marius does not know that Valjean is the man who saved his life in the sewers. Without Cosette, Valjean's life loses its meaning and he slowly withers away. Thénardier, however, unwittingly reveals to Marius that Valjean is his savior, and Marius and Cosette arrive in time to console Jean Valjean on his deathbed.
