Conrad channels Dostoevsky. Apparently Conrad did not care for Dostoevsky, but you wouldn't know it from this book. It is very reminiscent of Dostoevsky, in particular of Crime and Punishment. It's an interesting book. You can see what Conrad is trying to do, but it does not all come together and wonderfully gel as Conrad's best works do. That makes it overlong for what he acheived. The book is about Russian dissidents hanging out in Geneva and an enemy agent in their midst.
There is a puzzle to the book in that the narrator is an Englishman, most of the action takes place in Geneva, and the book is called Under Western Eyes. One would think from that this is a commentary on the West's understanding of Russia, but there is less of this than you would expect. Russia is presented as other to the West and Conrad does an excellent job of capturing the Russian temperament.
The book is very good in that while it sees the existing Russian society has oppressive and inhumane, it also sees the rebels as carrying the seeds of that same oppression. It was written a few years before the Russian revolution and anticipates it to a remarkable degree.
Its a good work. It might have been a great work if it all came together, but it doesn't quite.