Darker Than Black COMPLETE SERIES [Season 1, 2 & Gaiden] with OVA

Ten years ago, a bizarre phenomenon appeared in Tokyo. Three days later, two types of humans with supernatural abilities appeared: emotionless `dolls` that only do what they`re `programmed` to and wield the ability of surveillance, and powerful `contractors`, feared and hated by the humans that know of their existence. Rationally self-preserving and without the feeling of guilt, it`s not long before contractors are used as ideal assassins and weapons of war. Unable to analyze the phenomenon that created these beings safely, it`s decided that a huge wall be built around it, called "Hell`s Gate." PANDORA, an international research group, protects this wall and analyzes what little they can, while the government struggles to suppress dangerous contractors and the publics` knowledge of them. In all the police force`s efforts and doll-assisted surveillance of the city, one contractor continues to evade them. `BK201`, as the police force knows him, stands out as an exceptional killer, while those in the syndicate who know him as `Hei` see him as a powerful, yet strangely irrational contractor...