A young social worker by the name of Paige is mysteriously drawn to Prue's funeral, where she shakes hands with Phoebe. Phoebe has a vision of Shax attacking the girl on a rooftop and becomes obsessed with protecting her, while Piper is angry about Prue's death and tries to fight her destiny as a witch. Meanwhile, the Source learns from his oracle that there is another Charmed One, and goes to the surface to turn her to evil just as she's discovering her powers. Piper and Phoebe learn that Paige is their half-sister that their motherly secretly had with Sam, her white-lighter, and gave up for adoption to keep her safe. The Source disguises himself as Shane, Paige's boyfriend, and tries to tempt her into using her powers for evil. Paige realizes she has the power to move objects, similar to Prue's, but she orbs them to move them because she is half white-lighter. Meanwhile, a dogged inspector named Cortez takes over the Halliwell case from Darryl, and discovers the sisters' secret. He believes the witches are evil and tries to get proof of their powers to expose them. Piper and Phoebe have to convince both Cortez and Paige that they're the good guys, and Paige realizes that she cares for her sisters just in time to help them fight the Source. Meanwhile, Leo heals an injured Cortez, proving to the inspector that the witches aren't evil. The Source takes his revenge by stabbing Cole, and Leo can't heal him because he's half demon. With Paige's help, since she's half white-lighter, Leo is able to heal Cole. Paige hesistantly joins her new family and Piper and Phoebe use a spell to introduce their baby sister to her dead biological mother.