Maenads are figures from Ancient Greek mythology. They were the female followers of Dionysus, or Bacchus, and were positioned as part of the retinue of the God's bacchanals, often taking the title of priestesses. Maenads typically adorned themselves in the furs of an animal, and practiced mystical incantations. Inspired by their patron Lord, the Maenads would dance and drink and bring themselves to a state of ecstatic frenzy.
Maenads were presented in the HBO television series True Blood, which was based on a series of novels called the "Southern Vampire Mysteries" by author Charlaine Harris. One Maenad in particular, Maryann Forrester, was presented as one of the primary antagonists of season two of the show, and was played by actress Michelle Forbes.
Maryann Forrester was a powerful Maenad who was immortal and had the ability to transform her entire body, or selected parts into other creatures. Her chosen form of power was that of the bull, but she also turned her hands into cloven-hoofed bovine appendages. Marryann's ultimate goal was to become the bride of Dionysus, which could only be officiated at a large Bacchanal, ending with her corporeal death.
Maryann Forrester chose to make Bon Temps, Louisiana the site of her great wedding. She used her powers to charm those around her into obeying her commands, most of which involved conducting acts of extreme hedonism, even if such acts were in stark contrast to the personality of those under her sway.
Her wedding reception took place at the home of Sookie Stackhouse, and she had most of the town's residents in attendance; all of whom were intoxicated with Maryann's power. The only one who seemed to be able to resist her influence was Sam Merlotte, who was also a shape-shifter. In the end, Sam was able to put a stop to Maryann by transforming into the form of a bull and goring her before she could complete her ritualistic wedding.