The Nightshade was the secretary of the Mysterious Somebody during his reign over the PPC from 1992 to 1999 HST, having been promoted from her old job as a nurse after distinguishing herself during the insanity epidemic. During the Reorganisation she became dissatisfied with his rule and joined forces with the Orchid from the Mary Sue Factory in an effort to bring down her master. Her efforts were largely in vain due to the actions of Nyx Nightingale and the Sunflower Official; following the Mysterious Somebody's departure from the PPC, the Nightshade and the Orchid lived near the Factory, watching over his activities, and in 2006 they attempted to prevent his attack on Headquarters by capturing him, with the aid of the Gladiolus. Though this had some initial success, the Mysterious Somebody quickly escaped, killing the Orchid and forcing the Nightshade and Gladiolus to flee.
After the Black Cats' invasion and the death of the Wisteria, the Nightshade became the Department Head of the Department of Operations. She seems to have had some kind of relationship with the late Clover at some point in the past, going by her distraught reaction to news of his death.