Yuuko returns to her childhood home to confront a shadow from her past. Darkness has consumed someone who was once family-and turned her into a deadly enemy. But Yuuko has forged new bonds in Black Label, and with their support, she is able to sever this last link to her past. As Syringe threatens to unleash the next stage of infection upon the city, Yuuko and the team return to the "operating theater" once more