Charmed is a show about 3 witches that are sisters. Prue Halliwell (Shannen Doherty), Phoebe Halliwell (Alyssa Milano) and Piper Halliwell (Holly Marie Combs) play the sisters. In season 4, Paige Matthews (Rose McGowan) is found as there long lost sister and the savior to the power of three (after Prue dies).