I really enjoyed this book! I've also read The Hunchback of Notre Dame and, like that book, this definitely has a serious tone and can be melancholy or depressing at times, but I also feel like the story is told really well. The one downside for me was the chapters in which Hugo went into great detail on historical background or random information (such as a specific convent and the Paris sewers) which, while it pertained to the story in some way, also contained a lot of information and narrative commentary that I personally didn't need in order to enjoy the story itself. It did take me quite awhile to get through this book, but overall it was definitely worth it.