Summary (http://www.tv.com)
A young girl's nightmare becomes the search for the truth, a search that leads her to the secret and extremely dangerous world of Contractors and the Hells Gate. Hei and Mao try to protect Kana from the Contractors who are trying to silence her forever, while Kana clings to the hope of finding her father and piecing her life together again.
This, I thought, was a very good 25 episode anime. See if you like it too by watching the first episode:
Darker than BLACK Episode 1
I'll try to have more uploaded soon.