There is a long and cogent side trip into the history and uses of French religion. This is possible in a book, but not in a screenplay. They had to leave it out.
It also has a a long treatment of Cosette's time with the Threnediers. Hugo describes the way Cosette's mistreatment makes her into an unattractive child.She is not a blooming angel in rags, She is silent, frightened, sneaky. She, in her struggle to survive, has too keep what she can. She only comes to love Valjean later. This is consistent with modern understanding of neglected and abused kids. Hugo talks about how she had reached out for affection over and over when she was very small, and, not receiving it, gave up, shut down. Victor Hugo has it painfully right.
Strange to say it about such a long book-- but Hugo is an admirably tight writer. Nothing is wasted. We get to the part about the convent. Way back in the beginning of the book, Vajlean lifted the cart off the dying peasant, he got down in the mud in his mayor's clothing and saved a life, at the risk of his own. That is what put Javert first back on his trail. The good he did saves his own life later on. And it saves Cosette. He Is brought on a cart to the graveyard. He is interred, and rises from the dead, almost literally, he is born again, as a gardener at the convent. And it allows Cosette to be educated at the convent. The weight and value of his good deed is duplicated, balanced as a pair of silver candles. And it spreads out around him, to the other gardener, to the gravedigger and his poor family, to the blameless nuns. Like light, from candles.
Now we are done with most of the hiding and sneaking. Cosette is growing up, Valjean is safe for now. And the book is only halfway done. So far the book has had side trips to discuss, poverty, religion, justice, the penal system, child abuse, and the battle of Waterloo. Now it is going to talk about sacrifice, politics, education, self-delusion, the sewers of Paris, and love.
I am ready.