Darla is an evil succubus posing as the head of a dating agency. Not only is she using the agency to seduce and kill her male customers, but her presence has caused Phoebe's body temperature to rise, as she has a connection to Darla. The sisters' spell to catch the succubus results in Prue becoming a man, and at Piper's nightclub, the evil Darla appeared to Prue (as Manny Hanks) and made her move before she was stopped by Piper and Phoebe. She later escapes but is shot by Darryl and believed to be dead. However, Darla awakes at a coroner's office and kills Darryl's partner, using her elastic tongue.
In the episode's climax, Darla captures the masculine Prue in her loft, and again attempts to place Prue under her spell. Phoebe uses her connection to Darla to help Prue resist her, and once she does, Prue uses her powers to send Darla flying across the room. At that moment, the lit candles set Darla ablaze and killed her.