Disclaimer
I review based on the plot, characterization, emotional pull, animation and scene quality, and creativity in my anime movie reviews. I do not review by how short or long, or based on previous material, however I will sometimes reference previous material, such as the source anime or manga to make a point, but the review will not raise or lower in score based on such. Thank you.
Also don't expect a blog from me for a while, from the 4th to the 11th I'll be out of the town I live in on vacation and will be unlikely to blog because of such. I should have a blog about my trip to Las Vegas on the 13th unless I get busy with something else. Thank you again.
WARNING possible spoilers WARNING
So the plot is as follows. Inuyasha was at an island roughly fifty years ago, before he was sealed to a tree. He was marked for some reason, and ended up back towards the island. Inuyasha acts like he doesn't care about the kids there, but he keeps defending them. The island, trapped in time, only appears certain times, and half demons are thrown into a furnace to keep four war demon gods alive. The war demons have had their gems removed which lowers their power and makes them die slowly. Inuyasha finds their gems, and a clone of Kikyo attacks and opens the box their gems were stored in. Now all powerful, the demons attack the island for fun. Inuyasha and friends step up to destroy the demons and allow the half demon children to leave the island.
Unfortunately the plot is a bit convoluted here. The plot is functioning and works, but using blood to clone Kikyo seems silly in a way, and the furnace that the demons absorb energy from is not only silly, but it makes little sense outside of making the island tragic. Easily some larger problems but the plot works none the less.
The only thing I hate about the characterization is that characters pop in out of nowhere. Kikyo is tied into Inuyasha's history with the island, but she shows up outside of flashbacks to kill her clone, belittle Inuyasha making him feel guilty, and drop her bow with one arrow which literally saves the entire day (another part of the convoluted plot). Sesshomaru kind of does the same thing, he shows up for fighting one of the four demons only, and him being marked makes little sense to the timeline of the movie, was it before Inuyasha went to the island or the same time? I'm not sure.
Those may seem like a lot of problems, but it is only two characters. The rest of the characters manage to work just fine, Inuyasha develops emotionally, the kids grow stronger, the demons are characterized as evil demons just fine, and some of the more tragic elements work into these characters well. Heck, Kikyo randomly appearing out of nowhere builds up Inuyasha more, and her bow thing is more an issue with the plot.
Judging from me already mentioning some of the more tragic elements, this category is fine. The action is awesome, but there is also a tragic element as a child, a little half demon girl, feels that to avoid her friends dying before escaping, she has to sacrifice her own life by throwing herself into a furnace and burning alive to feed the four demons. Then knowing the fireflies are the trapped souls of everyone before them who burned to death is just more somber. There are a lot of sadness moments in the movie, and a lot of inspirational moments too, match that with great fight scenes with Inuyasha, Sesshomaru, and a decent fight with a monk and demon hunter, and you got some great emotional pull.
The animation is pretty good, nothing amazing but nothing really bad either, and the scenes flow together nicely. Nothing during any fight was overly confusing, and characters didn't randomly jump around the setting either. It was just done really well.
The villains are designed off of the Chinese legendary beasts (four symbols), the turtle, the phoenix, the tiger, and the dragon. their weapons are interesting as well, but the design of the plot and all the creative elements of the plot made the plot incredibly convoluted. Plot holes abound all because there was too much creativity crammed into one movie, not that the creative elements don't function, but similar to the plot, there is just too much creative element in the movie. Functioning, but actually harmed the plot of the movie as well as itself.
Out of all the Inuyasha movies, this one is probably the weakest structured due to an over saturation of creative elements which in turn harms the plot and makes it too convoluted. There is great characterization for all but two of the characters, and those two characters help emotional pull, either building up Inuyasha or just a great few action scenes. Action and emotional pull are great, and the scene quality is pretty good.
All and all, while you should be an Inuyasha fan to understand some of it, this isn't a bad anime movie. If you are a fan of Inuyasha I highly recommend watching this movie, but unlike other movies, it may be hard to understand everything if you aren't already aware of the personality of some of these characters. If you know Inuyasha is a heroic ass then feel free to watch and look into it, if not and you think he is suppose to be heroic all the time avoid and watch the series first. Still, pretty good movie assuming you know the characters, either from the previous movies, the anime, or the manga.