During the events of Blackest Night, Selina is attacked by Black Mask after he has been reborn as a member of the Black Lantern Corps. After he tells her that he plans on getting an emotional response before killing her, Selina steals a car and heads to the mental institution where Maggie Kyle is held, believing Black Mask is coming for her. Black Mask attacks the institution, and somehow awakens Maggie from her coma. Selina arrives in time to help her sister flee into the sewers. While on the run, Maggie angrily tells Selina that she ruined both of their lives the day she decided to become Catwoman. Devastated by her sister's statement, Selina fails to realize they have both been heading for a trap. Just as Black Mask is about to gouge Maggie's eyes out and shove them down Selina's throat, Harley and Ivy arrive and defeat the Black Lantern by trapping him in the stomach of a man-eating plant. Selina is helped to her feet by her friends, who tell her that Maggie has fled the scene. The next day, the staff members of the mental institution are shown discussing Maggie's escape, also mentioning that a nun that works at the hospital had been found beaten and stripped of her uniform. Maggie is then shown in the depths of the Gotham City sewers clad in the bloodied nun robes, muttering about her plan to kill Catwoman in order to free Selina's soul. Now calling herself Sister Zero, Maggie attempts to kill Selina, but ultimately flees after being defeated by the Sirens. She is last seen going over her options, now realizing that she cannot murder her own sister, and therefore must personally exorcise the "cat demon" from within Selina's body.