Phoebe wakes after a nightmare in which she vanquishes Cole.
In another location, a woman is seducing a man on a bed. She tells him that his wife is almost there and then she can watch him die. As the wife comes into the room, the other woman kisses that man. He begins to turn gray as smoke rises off his lips. He falls back dead on the bed. The woman, obviously in a trance, snaps out of the trance. She tries to revive her husband, but to no avail. The other women throws a couple fireballs around the room and knocks the wife unconscious, leaving her to burn to death in the fire.
Later in the morning, Cole and Phoebe are still communicating with one another, but Phoebe is trying to get the divorce to be the only thing they talk about. While they are talking, Cole sees the burning building and morphs there. He saves the woman. Phoebe looks at the television and sees Cole walking out of the building with the unconscious woman. Phoebe's editor presses her to get an exclusive interview with her husband, Phoebe reluctantly agrees.
Back at the manor, Paige is concentrating on getting her potions correct. Piper is upset that her baby is playing jokes on mommy's body by making Piper burp orb like bubbles. Piper calls for Leo to try and get support for all of the discomfort her body is feeling. When Leo materializes, they begin to argue that the other doesn't know what the opposite is going through. In the middle of the argument they see the television and the news coverage on the burning building. Leo recognizes the woman that Cole saved as a future white lighter. He decides he has to go be with her to see if the attack on her was demonic. This upsets Piper because she was hoping that they would be able to talk about the baby.
At a bar, the Siren tries to kiss another man to bring him to his death. At the last second the Siren overhears the news story and leaves the man. She has to get to the hospital and finish the job she started. At the hospital, Leo is waiting for the doctors to let him in to see Melissa, the women from the building.
Back at Phoebe's office, Cole tells Phoebe that he will only use his powers for good. She wants to believe him, but know that the evilness of the powers could make him turn on her or her sister just like before.
At the hospital, the Siren finds Leo and tries to lure him with her song. Piper feels the trance and Paige orbs her to Leo just in time to stop the Siren from killing him. Piper tries to vanquish the Siren, but the baby doesn't let her powers work correctly. The Siren shoots fire at Piper sending her out the window, but Paige turns into her white lighter and saves Piper. At the house, Leo asks if Piper vanquished the Siren. Piper tells him that the baby wouldn't let her powers work correctly. While Piper and Leo are arguing the baby decides to switch their powers. Leo has Piper's morning sickness, freezing and exploding power. Piper gets Leo's voices in the head, orbing and healing power.
The Siren, who was hurt at the hospital, goes to a dark healer in order to prepare for the Charmed Ones. She will destroy them through their loves for their husbands. Cole comes to the manner to warn everyone that the Siren is behind everything. There he learns that Piper is expecting and that Leo and Piper have switched powers. Phoebe refuses his help; he decides that he will go after the Siren himself.
Once he finds the Siren she puts a spell over him. Phoebe and Cole's love is still strong and once he is under the spell, Phoebe feels it too. Meanwhile, Piper is going to all different parts of the world helping Leo's charges, while Leo learns to make potions and try and control his new powers.
Piper feels that Phoebe is in trouble; she orbs Leo and herself to Phoebe and Cole. The Siren looks to have already killed Cole. As Phoebe goes to vanquish her with the potion, Cole destroys it with his power. Then he tries to kill Phoebe instead of the Siren. He succeeds in choking her to death. While he chokes her, Leo explodes the Siren and the spell is broken. Cole can't believe what he has done, Leo tells Piper to heal Phoebe, and she does.
Later, Piper and Leo apologize to one another for thinking that the other didn't understand what they were going through. They both realize that they have a lot on their plate, but that together they can accomplish it all. After this, the baby switches back their powers.
Cole apologizes to Phoebe for killing her, telling her that he never meant for that to happen. Phoebe knows that he didn't mean it, but wonders that out of the thousands of powers he has which one will end up killing her. Cole leaves feeling defeated, but not giving up hope.