Phoebe is at the mausoleum waiting for Cole. Prue meets her there and persuades her to come home, but Phoebe is worried, as Cole has not met her for over a week. Meanwhile, Raynor and Tarkin plot to turn Cole back to evil. Tarkin originally wanted to kill him, but Raynor thinks he could be useful to them. Raynor thinks that Cole has been "contaminated" by mingling in the mortal world for so long, but in doing so, he may have given them the break they need to kill the Charmed Ones. He has used his mind reading power to scan Cole's mind, and believes the only thing keeping him good is his human half's love for Phoebe. He decides the way to turn Cole evil is to turn Phoebe against him.
Piper and Leo plan a honeymoon in Paris. Piper prefers to fly rather than orb, and toward that end, alters Leo's birth certificate to give his year of birth as 1974 rather than 1924. Prue reports no word from Cole; Piper thinks Cole has been caught.
Raynor revives Cole. Raynor doesn't hold Cole responsible for the collapsed takeover of Luxirom--even if he was seduced by Phoebe. He sends him after a witch with an amulet--fully expecting that he'll warn Phoebe. Cole shimmers to Phoebe and tells her about his assignment. He explains that he must pretend to be evil until he can get disentangled from the Brotherhood. He also thinks Raynor is on to him. Phoebe begs Cole to let her and Prue follow him, but Cole thinks it may be a trap. He asks Phoebe to complete her power-stripping potion, after which the Brotherhood will not be able to find him. Phoebe runs into Prue, and asks her to scry for the witch.
Cole shimmers away and finds the witch with the amulet, Leeza, in her occult shop. He tries to steal the amulet, but it blasts him. He turns into Belthazor and the amulet tries to ward him off, but he is able, with some effort, to take the amulet.
Leo and Piper wait in line at the passport agency. Leo gets a jingle, upsetting Piper. She points her finger at the clock as she pissed that they have been waiting in line for so long and it blows to pieces, frightening everyone and Piper too.
Raynor finds Leeza cowering in her shop. He tells her that the fact she's still alive is proof Belthazor has gone soft. He blasts her with an energy ball to set Cole up. Phoebe and Prue arrive too late, but they don't believe that Cole killed her. Leo orbs in and explains that the amulet is half of a charm that if combined, more than doubles its protection power. A local coven has the other half. Leo believes the Brotherhood is trying to destroy the amulets, since they will not protect evil beings.
Cole and Tarkin are waiting in the Brotherhood's underworld lair when Raynor arrives. He asks Cole why he left Leeza alive, but Cole said he didn't want to risk tipping off the sisters. He also said that Raynor didn't order Leeza killed, but Raynor tells him he should have known Leeza was to die. Raynor orders Cole to steal the other amulet, and to kill the witch this time. Tarkin isn't sure if Cole will come through this time, but Raynor says he's got "insurance"--a glowing ball of unknown origin.
Prue wants to scry for the amulet's other protector, but Leo says the amulet wards off all magic--including scrying. Just then, they hear a noise in the kitchen. They find Piper covered with the remains of a watermelon. She says she was trying to freeze it when it blew up in her face. In frustration, she blows up a potted plant and the glass on the cupboards. Piper is scared out of her wits, but Leo, Phoebe and Prue try to comfort her. Prue gives her a pair of oven mitts, but that isn't enough to keep Piper from blowing up a kettle. Leo goes to the Elders to find out what's going on.
Just as the sisters are wondering where to find the second witch, Cole shimmers in. He looks somewhat haggard. Phoebe says they need one more ingredient for the power-stripping potion--something called "billings root." Cole doesn't know if he can hold on much longer, and begs her to follow him to the coven and stop him.
Cole finds the coven, and Tarkin then finds Cole. Tarkin tells Cole he'll feel a lot better after the witch is dead. Cole turns into Belthazor and goes in on the witch. Just then, the sisters arrive. Prue wants Piper to freeze him, but Piper is afraid she'll blow him up. Prue flings Belthazor away. The sisters run over to the witch. Tarkin throws an energy ball, but Piper distracts him by blasting a tree behind him. Belthazor throws an energy ball at Phoebe and the witch. The amulet protects them, but the force of the energy ball is enough to send them flying into the bushes. Prue sends Belthazor flying into a rock. Belthazor exchanges a glance at Phoebe, and he and Tarkin shimmer away.
The sisters take the amulet's protector, Janna, to the manor for safekeeping. Janna is gratified to finally meet the legendary Charmed Ones in person. Phoebe's arm is slightly injured, but she doesn't think Cole tried to kill her; she saw pain in his eyes, not evil. The sisters want Leo to heal her, but Janna thinks she can make a simple salve to do the job. The salve heals Phoebe almost instantly. The sisters ask for help with the power-stripping potion, and Janna tells them "billings root" is simply ginger. She helps Piper with the potion while Phoebe goes to look for Cole.
Raynor isn't happy that Janna is still alive, but Cole points out the sisters were there, and under the circumstances taking the amulet would have been too risky. Raynor and Tarkin are now convinced Cole has gone soft. Cole, at last, admits to Raynor that he still loves Phoebe and that he will not kill. Raynor, however, produces the glowing ball from earlier and says it contains the soul of Cole's father.
An enraged Cole lunges at Raynor, but is held back by Tarkin. Raynor promises Cole that he can have his father's soul if he kills Janna and fulfills other unspecified "obligations."
Cole instead goes to Phoebe at the mausoleum. Phoebe notices Cole is finding it harder to fight the evil; he starts turning into Belthazor. She drives him back to the manor rather than let him use his demonic powers.
Prue, Piper and Janna are working on the power-stripping potion. Piper worries she's being punished somehow. Leo orbs in, and tells the sisters that Piper's powers have actually grown. Her freezing power works by slowing down molecules, and a natural outgrowth is the ability to speed them up as well. Prue finds the amulets in the Book of Shadows; once they're joined, whoever has them has to use a spell to activate their full protection. Just as Janna finishes the potion, Cole and Phoebe arrive. The potion has to cool before Cole can drink it.
Prue and Piper head down to get some ice, when Tarkin shimmers in. Piper tries to freeze him, and winds up blowing up a potted ficus.
Tarkin throws an energy ball, but Prue deflects it into a wall and engages him. Piper tries to freeze Tarkin again, but instead knocks the bookcase onto Prue. Phoebe comes down to help. Piper tries to freeze Tarkin again, and this time, blows him up. Phoebe rushes upstairs to check on Cole.
Just as the potion finally cools down, Raynor shimmers into the attic and knocks Leo unconscious with an energy ball. Raynor then throws an energy ball at Janna. The amulet protects her, but the force of the energy ball is still enough to throw her into some boxes and knock her unconscious. Phoebe gets to the attic, but can't open the door; Raynor has blocked it. Raynor starts goading Cole to kill Janna. Prue has come too and tries to telekinetically open the door, but can't open it all the way. They see Raynor still goading Cole. Raynor waves his hand in front of Cole's face. While Phoebe watches in horror, Cole turns into Belthazor and kills Janna with an energy ball.
The sisters are very angry at Cole; they believe he not only killed Janna but knocked Leo out as well. Prue remembers the spell to activate the amulets' protection, and accuses Cole of only pretending to turn good so he could get the Book. Piper points out that evil can't use the amulets or touch the Book. Phoebe turns violently on Cole, accusing him of wanting to strip his powers so he can get past the Book's protection and use the amulets against them. Cole adamantly denies this, but the sisters don't believe him. He begs Phoebe to save him and give him the potion, but Phoebe curtly tells him to save himself and smashes the potion on the floor. Cole shimmers away.
The next day, the sisters are cleaning up the mess from the previous night's attack. Piper never really trusted Cole, but now thinks there is still good in him. Seeing what happened to Cole made Piper understand how it feels to have powers she can't really control. The sisters do a blessing for Leeza, Janna and Cole. Leo now has his passport, but Piper thinks it best to wait to go to Paris until she can control her new power.
Cole meets with Raynor, who hands over his father's soul. Cole turns on Raynor and stabs him with a knife. Raynor congratulates Cole on becoming evil again, just before he goes up in flames.