"The Melancholy of Haruhi Suzumiya" is a huge deal in anime. If one had to make a top-ten list of most important or influencial anime to the culture, it would be on that list. It isn't necessarily as great as one might think, but its effect on internet culture, anime fan-groups, and the high-school romantic comedy genre as a whole cannot be ignored. Anyway, it ended with its second season around 2009, and presumably would not be adapted further. This was probably for the best: the second season didn't add much, the feature film "The Disappearance of Haruhi Suzumiya" provided an emotional payoff that satisfied most fans, and there was really nothing more that could be done with further adaptions.But then it was announced: "The Disappearance of Nagato Yuki-chan" anime (based off the light-novel release of the same name) would premiere in 2015, almost ten years after the original series was broadcast. The characters everyone loved would return! It would be set in a alternate universe from the original anime, and focus on Nagato (at first, it was assumed Haruhi herself might not even appear) in a suspiciously-similar form as her alternate self from "The Disappearance of Haruhi Suzumiya" film. The producers were being coy, but surely this would continue the series we all knew and provide some closure! Right?Wrong. For the most part, this is a completely stand-alone series that has no ties to the main series whatsoever. All the science-fiction-fantasical-god-multi-dimensional stuff is no where to be found. This is a simple romantic comedy set in a high school. Nothing more.Which is not to say it is completely a waste of time. Nagato is a shy and timid high-school student, hiding behind her glasses and messy hair whenever her friend and secret crush Kyon walks by. It isn't too long before another girl named Haruhi, despite attending a different school in the neighborhood, starts hanging out with the group, taking over their literary club because she too wants to be with Kyon. Nagato is flustered by the whole thing, but through kindness and the help of her friends, she makes nice with Haruhi, and maybe gets a little closer to Kyon by the year's end.So yes, Haruhi and everyone else you remember appear in the show. The relationships are slightly different however, with Nagato's best friend Ryoko being the main side-character rather than Haruhi or Kyon. When Haruhi does show up, it gives a slight spark and energy that the initial episodes were missing, but she too has not committed herself to aliens or espers, becoming a more mild version of the version we recognize. About two-thirds into the show, there is a twist that seems to bring back the stoic Nagato fans remember, but not as an alien: any similarities is only through coincidence, and this too passes back to normalcy. Aside from a few easter-egg jokes in conversation (Ryoko makes a joke at one point about wanting to "stab" anyone who would hurt Nagato), there is nothing here to satisfy fans of the original series, not even the slightest hint.
Which is perhaps for the best, as the resulting show is generally much more pleasent to watch. The original "Haruhi" series was all over the pace tonally, going from offensive jokes and mean-spirited humor to true-romance and hardcore science fiction. With "Nagato," it is just romantic-comedy with some drama for effect. Rather than dreading or look-forward to the next episode, I emotionally felt somewhere in the middle, welcoming each episode onto my tv as I watched. However, the tone and general lack of plot makes "Nagato" a bit bland, and despite Nagato's generally sweet personality as a main character, I didn't particularly care about what happened. It is only slightly better than "meh," and to rate it any higher would depend entirely on your expectations: if you like simple high-school romance, this is one.The animation studio is... Satelight? Kyoto Animation became a wealthy studio almost entirely because of Haruhi, so its strange to imagine why even a spin-off show would go to anyone else (although perhaps the original creators didn't want to confuse viewers further into expecting any ties to the old show, or Kyoto perhaps felt the story was no longer worth their time). The character designs look slightly different, and the show as a whole doesn't particularly stand out. Everything just looks pleasent, rather than exceptional. The music is pleasent. Both the English and Japanese cast reprise their original roles from the main series, which is a treat to hear again, especially for the now more interesting Nagato, although otherwise there isn't much in the script for the actors to use. "The Disappearance of Haruhi Suzumiya" helped drive home the idea that the franchise could very well have countless parallel universes that diverge slightly from each other, and that one of them would be more idealized to suit certain characters. It can be assumed that the world we see in "Nagato" is that very same universe we see in that film, giving us more background to tie ourselves to it. Perhaps watching this new series and going back to that feature film will strengthen your appreciation for it. Other than that, fans would be severely disappointed, and those who go in blind will wonder what all the complaints are about. I admit I respect the creators for having the balls to make this, and despite its plainness, I have a slight soft-spot for it. If I had to go back and watch something from the now vast collection of "Haruhi" animation, "Nagato" is the first I would reach for.