The first part takes place in a new, mostly American VRMMORPG called Gun Gale Online (GGO). Unlike Sword Art and Alfheim, GGO has no magic, and for the most part the weapons you get are guns. This makes deaths much quicker and adds a certain element of dueling that can end in an instant. But someone going by the name Death Gun is somehow shooting people in the video game and they are dying in real life. So our hero Kirito joins the game to investigate the scenario. He makes a new friend/rival Sinon. We end up learning about her past and seeing Kirito's and his fellow ex-SAO members continue to live in the real world as well as in the virtual ones.
The second part at first is a side adventure within Norse Mythology and the idea of a video game having no true limitations on what could occur. After this adventure we see the life of Asuna and just how hard a life of riches can be. The responsibilities and stresses that can come with it. But mostly it is the meeting of a guild of players known as the Sleeping Knights. This small group wishes for her help to immortalize the impressive deed of defeating a floor boss with only their small numbers. They fight together and things about the people and the group are realized that bring into question the real world and some of the potential that virtual realities can truly have for people. Especially for people who may have certain disabilities or disadvantages in the physical world.
This second series is fascinating and quite well done. I think I still prefer the first part of the original, but in the end this second bit lived up to the path laid down by the original, and as I said it was more thought provoking. SAO II gets a 10 out of 11.