Netflix has once again released a series that has incredible potential, but has been undermined by horrible writing and extremely weak casting choices. Henry Cavill was an inspired choice as Geralt of Rivia, and obviously brings a lot of knowledge and fondness to the role. He gives the series a luster that is unfortunately quickly dimmed by the horribly dimwitted writing. Eels??? What is with the Eels??? Note: that didn't need a spoiler alert. If you've seen the series, you'll know what I am talking about, and if you haven't, you will know when you witness that silly travesty.
The sets are lush and well done, the costumes are good, and the music fits well with the setting. The exception to the music is when Dandelion goes from Medival to something akin to "Pop Harp". Grating doesn't even begin to describe it. I did like the action scenes, as Henry Cavill is very believable as a athletic monster slayer.
So overall, I give a 9 to Cavill and the great atmosphere of the series. The supporting cast are sporadic and generally weak, and rate no more than a 5 or 6. The writing, and in particular the scenes added to the script that were never in the original books, was extremely weak, and garnered no more than a 2 or at the most 3. I gave the show a 6. Mildly entertaining, but falls far short of the original books and the three Witcher games.