The premise of the game is that the Dead Three chose their human form avatars, who wanted to control a very powerful psychic entity called the Elder Brain via three magical items, however, little did they know that those three magical items gave the power for the Elder Brain to develop in to a more powerful force called the Netherbrain and it just waited for some fool, who would best the avatars of the Dead Three and take control of the magical items. Lo and behold, it is your main character and his/hers entire party composition, who got caught by the servants of the Netherbrain called the Illithid (basically evil squids) and were operated on. They enbedded in to your cranium a worm, which was supposed to turn you and your friends in to Illithids, but it didn't, because a rogue Illithid decided he does not want to be controlled by the Netherbrain anylonger. So, the whole main premise is you and your party searching for a cure, which leads you to battle the big bad Three and the Netherbrain.
On paper, this sounded good, however, the execution was less so. The story outside Act 1 and certain side quests in Act 3 was mostly boring. It wasn't bad, just boring. The companions, I might have liked them, if not for the fact that without any introductions or getting to know each other better, they all seemed to proposition themselves to my character, and when being mostly turned down, they had nothing substantial to add until Act 3. Well, Shadowheart was mumbling something about Shar's influence (her patron god) towards the end of Act 2, but I did not really listen, because a failure of a certain quest in Act 2 might force you to not really pay any what little attention to the silly plot the game had. And, believe me, ninety percent of players will fail that quest the first time around, and all of their hard work during Act 1 will be for nought (of course, if they decided to go the good route).
What really carried this game till the end for me was the combat, even though I'm not a particular fan of turn-based-combat mechanics, but you had a vast variety of skills and magic at your disposal that dispatching enemies was more or less fun. Also, I liked the fact that 9 times out of 10 you could bypass the cinematic cut-scenes (the enabling of which might have lead you to more difficult fights) by simply attacking before hand or running around while invisible around the boss and attacking from behind. Invisibility skill is really OP'd, because, if you detach yourself from your party and just walk around the npc, whose cut-scene should be triggered, you'd essentially brake the game to your favor.
Now, on to the bad technical side of things. Until Act 3, the most bugs that I have experienced was no music. People on forums were skeptical of this, how could I not think that BG3 soundtrack is the next best thing? Well, for one thing, up until Raphael's fight in Act 3, I never heard any music in the game, after it, the music suddenly appeared (so, we are talking about at minimum 40+ hours of no music). However, once Act 3 came... well... every time I went in to a new area, I had to wait up to 20 seconds until the game engine renders the area around me, and it did not matter that I was in 2x2 cellar or a sprawling city. Just for this reason I could have quit playing, because it's not normal. While the latest patch better the load times of the game itself for me, but this did not change anything regarding the loading of models in Act 3.
But the biggest issue with the gameplay itself was that inventory management and party system was not user friendly. Your inventory system is directly tied with the characters you have currently in your party, there is no party-wide inventory system in the game, so, if for example, you find weapons and armour suitable for a rogue, and you do not have the rogue in your party, you every time have to go to your camp and switch out characters. And this leads to the party system. Every time you want to replace your full party, you have to dismiss a character, but in order to do so, every time you have to listen to their moaning about how their are really useful to you and how they are disappointed that you are leaving them in camp. For this reason alone, my entire party composition never changed since the ending of Act 1.
That being said, I respect Larian for their ambitious game design. It's just that had I known what I was going in to past Act 1, I might have waited a couple of years to get the game at a bargain bin price.