The psychotic Meg Kinderly
Meg Kinderly (Jenny Seagrave) is the main villainess from "The Killer," episode 3.03 of The Hitchhiker (airdate November 12, 1985).
The episode introduces Meg as a paralyzed young woman lashing out at her parents as they were preparing for a long vacation, leaving Meg in the care of their servants. Later on, Meg emerges from the swimming pool and upon entering, she is shocked to see her parents, sister, and servants all shot to death, and later arms herself with her father's shotgun for protection. She later encounters Jack and asks him who the culprit was, only for Jack to die before he could answer.
After her brother Jonathan enters, Meg panics and hides from him, later accusing him of committing the murders. The episode's climax saw Meg lock herself inside one of the rooms, with Jonathan attempting to get through to Meg and tell her to remember what happened. At that moment, Meg's panicked state quickly becomes subdued and ominous, as the truth as revealed: she committed the murders. Having had enough of her family's emotional neglect, Meg snapped and shot both of her parents, her sister Patty, and her two servants--Sara and Jack--to death, using her father's shotgun as her weapon of choice. Jonathan enters the room to get through to Meg, only to see Sara's body on Meg's wheelchair. In the final scene, the evil Meg snarled to Jonathan that he was "just like the others" before shooting him to death.