I think that Wells is an underrated writer and that this book is underrated within his works. It is better than The Invisible Man and almost as good as War of the Worlds, which is in many ways a companion piece to this work.
The story concerns two men Mr. Bedford, the narrator and the scientist Cavor who journey to the moon. The book is superficially told as a turn of the century British boys adventure, but it is really a satire of capitalism and imperialism, and to some degree the human condition. The narrator who frames the narrative, presents himself as an adventurer, but he is really a violent, self-serving opportunist, who abandons his colleague.
Cavor represents Wells consistently ambiguous view of science and as such he is an ambiguous figure and his invention of the anti-gravity substance Cavorite is similarly ambiguous. Wells' loves the grotesque and his description of the lunar landscape, its flora and fauna and the Selenites that inhabit it are good. The book starts off OK, but gets better and better as it goes along. The communist society of the Selenites is contrasted. Wells is too good a writer thopugh, not to show the pitfalls of that society. There are many bad things about it and this contrast is reminiscent of the Eloi and the Morlocks, which are not a simple division into good and evil either.
Mine is the Penguin version and it has an excellent introduction by China Mieville, who I had been thinking of reading and now certainly will.
Overall this is a lost classic and why it is not better well know, I do not understand. Wells is still the best science fiction writer.