This is a science-fiction classic...I suppose. It was ok, but nothing special. Dr. Moreau has figured out how to change the characteristics of various animals by grafting parts from one onto another. Perhaps he also plays with their blood via transfusion. Whatever, he can turn sloths and pumas into semi-human creatures, which he then dominates by means of pain and a set of rules, known as the LAW. Something like that. He does all his work in secret on an Island in the Pacific, somewhere west of the Galapagos.
The main character is a poor schmuck who ended up on the island because of a ship wreck. I dunno, he is not a particularly engaging personality. Neither is anyone else in the book. Some of the ideas are interesting, I suppose, but dated. Our knowledge of science is much improved from the heady days of yesteryear when much scientific inquiry was little more than fantasy.
So, what I'm saying is the book is ok from a historical point-of-view, and is not a bad read. It's just that there are lots of better things out there that one could be reading. This was my third H.G. Wells' book, and so far, I'm not particularly impressed with him. Dickens stands well the test of time, Wells, not so much.