The series seems to toy with the idea with being a mystery and a romance but in the end discards such endeavors. This is quite disappointing as the second half of the series destroys whatever good will the first half produced.
If you're looking for a good thriller series, there are plenty of better ones out there. If you're looking for a romance/harem (noticing that there are many cute girls in this... Rimi...), this is not it.
Animation:
The animation is top notch, crisp and clear. Battle sequences are well done though sometimes it pans away just at the critical moment. There is a bit of CG used but it is done in a manner that doesn't detract from the overall quality of the series. The series uses colors of day and night well to define the mood throughout the series. The presentation overall is solid.
Sound:
The series starts off with a very catchy OP and presents a good concluding ED that serves to "calm" the viewer from the "Chaos" of the episode that just ended. The BGM and numerous effects give an errie feel that the series demands. This is at the sacrifice of having any unifying theme underlying it all. There are numerous VAs in this, all of whom give their respective roles a lively personality. Though the main character is supposed to look like a wimp, I think they overdid it a bit.
Story:
Chaos; Head starts at a thriller that plays with your head. What is reality? What you actually see happening in the series vs. just a delusion of Takumi? It's really hard to tell at times but it sure makes the first half of the series fun.
The show is about an otaku named Takumi that strangely lives in a tiny shack-like container at the top of a building. Soon, events start happening that are outside his control and he is eventually forced to take action and figure out what is happening around him.
The early part of the show is very enthralling but once the truth of what is happening is out, the story doesn't try to add any additional twists, falling to a linear, very predictable, progression. And though there are many powerful (and cute) supporting female characters, they are by no means used anywhere close to their potential in the series. It's as if it was shooting for a romantic sub-theme but then shoved it aside.
The final climax at the end was very predictable and the show ends rather quickly after that. There isn't really an explanation for what happens after the climax, it just is. The lack of any falling action makes me think that the production team got lazy... This series definitely deserved more than what it ended up being.
Character:
Takumo is a detestable character. He is an otaku and a wimp who cares only for his games and Seira-tan anime figurines. When anything becomes difficult, Takumo just runs away. His pitiful nature caries throughout the series as he finds himself in the middle of the largest crisis Shibuya has ever faced.
Despite his personality, Takumo is probably the only non-static character in the entire series. Though the other supporting female characters are all unique in their own way, only a bare-minimum approach was used in their development. Several of the girls don't have any exposition on their past at all. This may have been to keep the mysterious feel early in the series but even once everything was clear, the supporting females only felt like additional baggage that the series just carried for the heck of it.
Value:
If you're looking for an enthralling thriller, enjoy the first part of the series. But then you might as well throw it out once the initial mysteries are solved as the latter portions of the series are very linear and lead to a conclusion that is both predictable and (even worse) poorly executed.
