Crystal Gregory is a beautiful new teacher at Sunnydale High, who also happens to give Buffy panic fits whenever she's in the same room as her. Buffy can't sense anything unusual about the teacher and begins to wonder if she's losing her mind. But lately, Anya and Michael seem to be getting awfully close to Crystal and would appear to do anything for her. While out for her usual patrol at night, Buffy has two strange encounters; one, a man is completely incinerated by red and lighting and the other being a girl from school who has a burn mark on her neck in the shape of the symbol for infinity. As soon as Giles gets cracking on his books, he finds out that Crystal is in fact Shugra, a powerful primal witch which is trying to activate the source. She needs a coven of 13 willing people to participate in order to draw the proper energy, unfortunately, it seems that Willow is one of those people.