Darker Than Black: Gaiden

Gorou and Lostman at the peak of Mount Everest see the ISA Space Station in the sky above and become determined to go into space. ISA begins a program to research and obtain a new energy source which has been discovered on the moon.

A long time in the future from an already distant future, the United Planets has waned in significance, and the Empire has also collapsed due to internal strife. People all across the universe now lead idyllic, peaceful lives. Banjo is one of them, a boy collecting debris on the outskirts of the planetary walls, when he ends up salvaging a broken-down spaceship and finds a frozen girl inside. He soon finds the hands of evil targeting her, and the entire galaxy being whipped into a furore. And no wonder, because she is Goza the 168th, a girl who holds the key to the entire universe's fate.

A princess finds a ancient power and it allows her to summon a dinosaur demon that will obey her. However, she gets attached to it's head and she is his brain and she must save her captured sister.

Saved by Merlin, a wise magician, and brought up by a retired knight. When he was 1 5 years old, he happens to prove that he is the person to be the king of all Britain, by drawing out the sacred sword, Excalibur, which no other men was succeeded to draw out from the iron stand. But in order to become a real king, he has to beat Lavic who is under the protection of Medessa, an evil witch. Merlin tells Arthur that he has to find out the Holy Shield to bend King Lavic and Medessa. Thus, Arthur goes on a journey to seek the Holy Shield. On the way he runs into four boy knights-Lancelot, Perceval, Tristan and Guerrehet, who hold up the same ideals as he does. They make a pilgrimage from one country to another in search for the Holy Shield, helping some common people who are distressed by bad aristocrats under the influence of Lavic, and subjugating some bandits.

After a young girl's mother dies she is moved from the city to the country where she accidentally meets a synthetic alien 'Figure' that takes the guise of a twin sister and begins attending school with her.