Phoebe, Paige, Jason and Richard are having after-dinner conversation. Paige pulls Phoebe aside and urges her to admit to Jason that she is a witch. Leo orbs in and tells them that Piper is under attack. Piper is battling Swarm Demons that keep coming back after she blasts them. Phoebe and Paige orb away to assist Piper. Jason notices that the sisters are missing, and then all three orb back in front of him.
Richard blames himself for the sisters' exposure, believing his and his family's bad karma was at fault. Phoebe thinks it was her karma instead, as she has kept her status as a witch secret from Jason. On consulting the Book of Shadows, Piper and Paige learn that Swarm demons are spawned by a king and that they will need the Power of Three to kill the king.
Phoebe approaches Jason but he is unwilling to talk to her. He is remembering all the strange occurrences that have surrounded Phoebe. Meanwhile, Piper and Paige find the Swarm demon king.
Richard reads the Book of Shadows while the sisters are away and casts a spell, attempting to remove his bad karma. Phoebe walks into the manor and a spirit enters her; she has a vision of being in front of a French-speaking firing squad. Piper and Paige come in and find Phoebe in a revealing dress and at times speaking French. Piper and Paige realize that Richard has cast a spell and that Phoebe was affected somehow.
Jason is speaking to shareholders about a merger with a French company, when Phoebe comes in, performing a sexy dance and removing her dress. Jason is mortified. Phoebe pronounces a curse and champagne bottles pop open, dousing the shareholders. Frogs appear from nowhere. At last, Piper walks in, freezes the room and calls for Leo. Phoebe freezes with everyone else, something that doesn't normally happen to witches. Leo orbs the sisters away.
Back at the manor, the sisters figure out that Phoebe has gained the karma of Mata Hari, as both have led double lives. Shortly after, Swarm demons attack. Paige and Piper fight off some of them, but Phoebe defends the demons. The demons shimmer away with Phoebe. Phoebe meets the Swarm demon king and suggests creating some bad karma for the sisters by killing Jason.
Richard meets Jason and admits that he, too, is a witch and that her strange behavior is due to his spell. He presents Jason with a potion and urges him to throw it when he sees Phoebe, promising that she will then be back to normal. Jason enters his limousine, dogged by reporters, but Phoebe is waiting for him there. Two Swarm demons shimmer in and then take him and Phoebe away.
Paige and Piper enter the lair of the Swarm demons. Phoebe has stood Jason up against a wall and a number of swarm demons have formed a firing squad to execute him. Jason throws the potion and Phoebe is back to normal. Phoebe repels the demons' fireballs by channeling their power and the other sisters orb in. They say a spell and vanquish the Swarm demon king.
Phoebe meets with Jason and he is as sorry as she, for being wrapped up in his career and dragging Phoebe around the world. He suggests that they "take some time"; they kiss and she walks away.