First off, the Product Description does this book a great disservice when it says: "Geralt de Rivia is a witcher. A cunning sorcerer. A merciless assassin. And a cold-blooded killer."
Well...he's not a sorcerer...at least not in the sense they mean in the book. He's not an assassin - they actually go through great lengths in the book describing how witchers are not hired killers. And he is by no means a cold-blooded killer. I don't think it's too much a spoiler if I say I can count the number of things Geralt kills in the book on one hand. A witcher, as described in the book, is supposed to save lives rather than take them.
I don't know why the publishers chose this description, but I guess the description "A philosophically-minded warrior confronted with moral ambiguities" would not sell many copies.
Now the review: This book chronicles the adventures of Geralt of Rivia in a series of loosely tied adventures. A convoluted way to describe his job would be to say he slay monsters, but a better way would be to say he helps people with monster troubles, resorting to violence as a last resort.
The book is written in short story form with a overarching mini-story which acts as a segway between each story.
The book itself, honestly, falls flat for about the first half of the book. I felt quite a bit was either lost in translation or the author was trying too hard to define his character.
The book becomes much, much better once Geralt's foil, named Dandilion, is introduced. I would also say that the very last of the six short stories, named "The Last Wish," is superb and more than enough to warrant a purchase of this book.
Overall, I would highly recommend this book to fans of the computer game, The Witcher,
As for those look for a grittier take on fantasy, I would say this is a good read, but there are better books out there.