Anime following the adventures of a brutal gang of trained assassins. The girls of the Social Welfare Agency aren't merely trained to be assassins, they are built for the purpose - assembled from the remains of human corpses with the aid of cybernetic implants. The eldest assassin, Triela, is the most dedicated killer of them all and dispatches her targets remorselessly. But has Triela finally found her match? A faction at war with the Social Welfare Agency, the FRF, have a brutal trained killer of their own, Pinocchio. Triela and Pinocchio seem certain to meet at some point. Who will give way when an immovable object meets an unstoppable force?