I'm surprised there isn't already a thread about this series considering how huge it is.
Kara no Kyoukai - The Garden of Sinners is a novel by Nasu Kinoko, the author of the visual novels Tsukihime and Fate/Stay Night, the anime adaptations of which you might be familiar with. There are some connections between the series, but nothing substantial. Kara no Kyoukai is about humans with special powers and follows Ryougi Shiki (voiced by Maaya Sakamoto), a girl with two personalities whose eyes can see the death of everything in existence and kill it by destroying its origin, as she becomes involved in a series of strange deaths.
The novel is being adapted into a series of anime movies by ufotable. Each movie corresponds to one chapter in the novel and averages at about an hour each. The movies are receiving theatrical releases, with the seventh one opening later this year. So far, the only way to watch these is to wait for subs of the DVD releases, with the fifth one just released in January.
The production values on these things are amazing. The music, animation, and art are all top-notch and I'm amazed that there's no Blu-ray release so far (I suspect that we'll see them coming out once they're all out on DVD). The story is kind of confusing, especially if you're not familiar with Nasu's writing style (which I hear is strange) or TYPE-MOON stuff in general. This isn't helped by the fact that the story begins in the middle of the story and jumps back and forth in time.
For actual impressions, I thought the first two movies were pretty cool. The first one was confusing but had a really nice action sequence, while the second one provided and introduction and exposition, but not nearly the same amount of action. It's not until the third one, which I just finished, that it really drew me in. The third movie has a nice mix of reveals about the setting and an excellent action scene.
Anyway, it's worth taking a look, even if you decide it's not for you, just for the amazing visuals and soundtrack.