S2, E2: When Phoebe has a vision of herself being burnt to death, the sisters travel ten years into the future to learn what happened. Only to discover that she used her powers to kill Cal Greene, causing a local D.A. named Nathanial Pratt to begin modern day witch trials as a platform for political office. Meanwhile, Prue and Piper try to save Phoebe, but they both are surprised and somewhat disappointed to learn how their lives turned out.