Season 04, Episode 16:
The Fifth Halliwell
The sisters, Leo and Cole have a night out in P3. Paige wants to leave; she's a bit uncomfortable at the two couples kissing each other. Cole convinces her to stick around. He gives Piper and Leo a gift—reservations at a high-priced hotel in Hawaii. Suddenly, Cole spots the Seer out of the corner of his eye, excuses himself and flames to the Underworld. Cole isn't happy that the Seer interrupted his night with the family. However, the Seer has prepared a tonic that will make Phoebe fertile. It will also override any preventative measures Phoebe may have taken in case she found out she was married in a dark wedding, ensuring the child will become evil. Phoebe's favorite sweet is chocolate, and so the Seer mixes the tonic into a box of chocolates. Cole must impregnate her at the harvest moon, which is the next night.
Phoebe wants to buy some lingerie for Piper. She asks Paige to come along, but Paige has to go to work. As the sisters head out, Cole pulls up in a Porsche convertible. He's gotten a new job at one of San Francisco's top firms. This surprises Paige; she'd gotten him a job as a legal aid attorney but it didn't last ("Lost and Bound"). Cole pulls out a box of chocolates, and tells Phoebe he's reserved a honeymoon suite. Phoebe decides to get some lingerie for herself. Piper has to set up for Rebekah Ryan playing P3 that night, but Leo offers to cover for her.
While Phoebe and Piper are shopping for lingerie, they find a woman, Karen Young, wandering confused in the street. Piper freezes the scene and Phoebe tackles Karen just as a car zooms past her. Phoebe has a vision of Karen being attacked by a demon.
Paige tells one of her coworkers, Lila, that she doesn't trust Cole. Just then, Phoebe calls her and asks her to help with Karen. Paige heads to the manor.
Cole is talking with the Seer at the manor. The Seer is concerned Phoebe didn't take the chocolates right away. Cole hears Piper and Phoebe walking in, and glamours the Seer into a man. Cole introduces the man as his law clerk, Mike, and hustles him out the door. "Mike" walks outside and flashes away.
Karen tells Piper, Phoebe and Cole that she doesn't remember anything past saying goodbye to her husband the night before. Phoebe pulls Cole aside and tells her that her vision was of something that already happened. She thinks the demon might attack again, and wants to postpone the honeymoon. Cole offers to help, and slips one of the chocolates into Phoebe's mouth. Piper grabs one of the chocolates as well, and she and Phoebe head upstairs to consult the Book of Shadows. Cole asks Karen what happened. She still can not remember. Suddenly, Cole comes up behind Karen and holds his hand above her forehead. Cole's hand starts to glow. Karen screams at Cole to stay away from her. Cole turns around and sees Paige in the living room entrance; she saw the whole thing.
Piper and Phoebe find that Karen was attacked by a power broker, a purveyor of demonic powers. Humans can't handle demonic powers; they become confused and eventually die if the power is not withdrawn. There is a potion that can accomplish this. Cole waves his hand at his pager, and heads out. Karen is desperate to get to work. She fears her boss, Elise, will fire her if she doesn't get there on time. She works at The Bay Mirror, and Phoebe heads there to cover for her. Piper heads to the herb shop to get some ingredients. Paige tries to tell Piper what she saw Cole doing, but Piper won't listen.
Paige tries to get Karen to talk about what Cole did to her, but Karen is afraid to talk. Just then, Leo—or so it appears—walks in. Paige tries to tell "Leo" what she saw, but "Leo" won't listen either. "Leo" walks outside and flames to the Underworld; he turns out to be Cole in a glamour. Cole changes "Mike" back into the Seer. Cole discusses his plan to discredit Paige. He plans to get a power broker to infect Paige and then accelerate her slide so she won't trust her sisters enough to warn them. Cole summons a power broker, who initially doesn't recognize Cole until his eyes turn black. Cole promises him great power if he infects Paige.
Phoebe goes to Elise at the Bay Mirror. Karen is the paper's advice columnist, and Elise isn't willing to bend the deadline for her. Phoebe starts to write the column for her, but gets stuck and calls Piper for help. However, Piper is making out with Leo in P3, and can't help much (due to the spiked chocolates).
Karen grows increasingly paranoid and tries to run out of the manor, but Paige blocks her. Karen leaps at Paige and bolts for the door, but Cole comes in and grabs her. The power broker smokes in and throws a glowing ball at Paige. Cole tackles the power broker. Paige goes to help Karen, but suddenly Karen spews acid from her hands, severely burning Paige's arms. Piper and Leo orb in, and Piper blows up the power broker while Leo heals Paige.
Piper calls Phoebe to warn her that Karen might be heading to the Bay Mirror. She and Leo head back there in case Karen shows up. Cole "accidentally" knocks the potion over.
Phoebe has completed the column just as Karen barges into the office. She spews acid at them, but Piper jumps out of the way while Phoebe levitates. The spray melts Karen's computer. Piper freezes Karen, and she and Leo stall Elise while Phoebe pours the potion down Karen's throat. Elise is impressed with the column.
Paige accuses Cole of being a demon, but Cole blows it off as paranoia—even as he throws fireballs at her and fire blazes in his eyes. Paige tries to rush at Cole, but is forced to back off when Cole raises a flaming force field around himself. Paige trashes the attic and blasts a small doll house with her demonic power.
Later that night, Paige orbs to Cole and Phoebe's hotel room and tries to attack Cole. Phoebe tells Cole to go for a potion in her purse, and Cole "accidentally" drops it. Phoebe calls for Piper and Leo, who orb in from Hawaii. Piper hits Paige over the head with a candlestick. Leo tries to heal Paige, but can't. Piper thinks that Paige's concerns about Cole were due to power brokers. Cole suggests going to the Underworld and get the power brokers to remove the power from Paige.
The power brokers are in the midst of trading powers when the sisters, Cole and Leo barge in. The power brokers bow when they see Cole, and they do as he and the sisters ask and remove the power from Paige. Piper then blasts the power orbs. Paige can't remember anything.
The Seer doesn't know why Cole saved Paige, but Cole points out that Paige has no memory of what happened and probably can't threaten them anymore. The Seer fears Cole's humanity is welling up again, but Cole thinks all will go according to plan once Phoebe is pregnant.
At P3, Karen comes to the sisters and says she's going to tell Elise that Phoebe wrote her column. She's going to spend more time with her kids, and is going to suggest that Phoebe must be hired in her place. Paige can't remember why, but feels she can't trust Cole. Phoebe thinks that Cole was the object of Paige's demonic rage because she already hated him.