Valjean confessed the truth of his past to Marius and insists that after the young couple are married, he must go away rather than taint the sanctity and safety of their union. At Marius' and Cosette's wedding the Thernardiers try to blackmail Marius. Thernardier says Cosette's "father" is a murderer and, as proof, produces a ring which he stole from the corpse in the sewers the night the barricades fell. It is Marius' own ring, and he realizes it was Valjean who rescued him that night.