The novel Les Misérables by Victor Hugo explores many themes of social injustice--including class conflict, human rights, and the role of transformation in the course of a life--through the lens of the revolution in Paris of 1832.
The book follows Jean Valjean, a man who serves nineteen years in prison for stealing a loaf of bread to feed his starving family; four of those are for the original crime, and the other fifteen are a result of an escape attempt he made. This punishment all but destroys Valjean's life and is a testament to the monstrous way in which the judicial system worked at the time... punishing those who were the most underserved in the community (the starving, the poor, the homeless, etc.) for crimes that essentially were committed out of necessity.
This system is predicated on the oppression of the working class; as a result, the novel takes place amidst the backdrop of revolution, with students and workers uniting for the liberation of the poor and socially downtrodden.
We see Valjean's character shift over the course of the novel, beginning with the act of kindness of a bishop who forgives him after Valjean desperately steals again after his release from prison. Valjean goes on to try to lead an honorable life and to leave his conviction behind him, becoming a manufacturing titan, taking care of the young orphan Cosette, and serving the community. Despite the suspicions of Javert, the police inspector, Valjean manages a true transformation and maintains a life of good work and values.