Charmed is about three sisters, who discover that they have inherited witchcraft powers from their mothers side of the family, and become 'The Charmed Ones', a formidable force for good in the fight against evil. They are strongest when working together as the 'Power Of Three'.

Initially the Charmed Ones are Prue, the eldest, Piper, the middle sister, and Phoebe, the youngest and most rebelious of the three. They later discover a fourth sibling, half sister Paige.