This is probably the best adaptation of Les Miserables out there. It unfortunately doesn't have an English translation as of me writing this, but for those of you who speak enough French to understand most stuff with a little help from google translate once in a while, the French translation of this manga is great.
Most people are at least passingly familiar with the plot of Les Mis. It is one of the most adapted works of all time, and one of those adaptations is one of the most successful Broadway musicals of all time. Unfortunately, the very nature of adaptation means that a lot of stuff gets left out. This is especially unfortunate in the case of Les Mis because the original is somewhat hard to read for a lot of people due to Victor Hugo's tendency to ramble about tangentially related topics. This adaptation is a great solution for those who are for whatever reason unable to read the book but at the same time wish to experience the story in as close to its original form as possible.
This adaptation is incredibly accurate. Some things are told in a different order than they were in the book, but the events as they happened are largely unchanged both in content and tone/theme. The first two chapters are dedicated to Jean Valjean's backstory, and the third is about Bishop Myriel. This is the opposite order of how things are introduced in the book, but the chapters are still incredibly accurate. So much stuff that's left out of most adaptations is shown here, like the bishop's sister and maid, Valjean covering for his nieces and nephews when they steal food, and Valjean being attacked by dogs when he tries to take refuge in a doghouse. It's clear that the author of this manga had a great level of respect and love for the work he was adapting.
In addition to being incredibly accurate while cutting out a lot of rambling, the art and symbolism in this manga is also incredible. There are a lot of things I could point to as an example of this, but my personal favourite is two pages that happen after Valjean is forgiven by the bishop. He is shown roaring in pain, a lion biting his neck and chains around him breaking. Then as the panels progress he begins to grow younger, turning to a young man, a child, a toddler, and finally a baby. As he grown younger his expression changes, and his scream of rage and pain turns into the crying of an infant. When he's a metaphor baby, the bishop comforts him by holding his hand. As this is happening, Jean Valjean is wondering who his is, and the bishop's voice says "Your name is Jean Valjean." I'm probably not describing this very well but it really needs to be witnessed firsthand. This sequence of Valjean being symbolically reborn is so good and such a great representation of Victor Hugo's intentions and work.
If you have any interest in the story of Les Mis, whether you're a long time fan of the book or you've seen the musical's movie adaptation once at the insistence of a friend, then you should definitely read this manga. The style differs from that of the book, but the substance remains largely unchanged.