Darker Than Black: Gaiden (OVA)
Tells the story of what happened to Yin and Hei between the first and second instalments.
Genres: Action, Animation, Science Fiction
Directors: Daisuke Chiba, Tensai Okamura, Toshinori Narita
Writers: Sean Whitley, Shotaro Suga, Tensai Okamura
IMDB: tt2104011