"Look, Geralt: humans, monsters, easy to mistake one for the other."

The Witcher's world is one of grey areas. There rarely are any clear moral choices. Good and evil are mostly a matter of perspective. Even the famous "Witcher neutrality" might very well just be an excuse to not have to make a choice.

And thus Geralt of Rivia, a mutant who has lived through several human lifetimes, after having suffered a near fatal injury and losing his memory in the process, is given somewhat of a fresh start in this world. A world filled with monsters, the ones with claws and fangs to rip you apart in the dark, but also those who walk in plain sight, crafting their more sinister schemes hidden away from the public eye.
A cultists' attack on the Witchers stronghold by a powerful opponent and the pursuit of their leader soon leads him deeper and deeper into the affairs of both humans and the outcast other races. If only they were mindless beasts to be slain without a second thought...

This is a game that is by now over a decade old. And on top of that, it's the very first game of a back then tiny studio of polish developers. And as that, it's rough, very rough around the edges.
The combat, even back then, is horrible at first and, even once you get used to it, although not complicated still not enticing. The english voices often seem poor (but considering that this game was made for the polish market first and only, and the international release just an afterthought, and budget was miniscule, it's acceptable, certainly not worse than Oblivion's crazy all over the place voice acting). The graphics are dated by now, but luckily there are a few mods to take care of most of it. Inventory management is barebones. The storytelling is often choppy and somewhat amateurish.

So why even recommend this, if all of those parts aren't great or even good at times?

The story itself, it's turns and twists, the decisions to be made, the care given to each quest, main and most side ones, are what truly makes this an RPG worth your time.
It is crystal clear that this is a labour of love: the people who made this loved the Witcher novels, and videogames in general as well. And keep in mind that this is their very first game, and not a simple one at that, but an in depth RPG. They tried to do it all, and even though they failed sometimes, they still get the most important parts just right.

The world oozes with lore taken from the books. The story, even if lacking in execution at times, is highly ambitious and captivating. Every nook and cranny is filled with mostly memorable quests and things to discover. Even reading journal entries is rewarding. Choices actually matter. And on top of that the finale really pays off, not feeling like an afterthought at all.

If you're a fan of RPGs and don't mind some by now antiquated mechanics, this is a game you definitely should play. And if you're newer to the genre, I'd say it's still worth looking past the game's shortcomings to dig a bit deeper, as you might very well discover some rare loot underneath the surface.