The Halliwells go to Magic School on the trail of evil, but Phoebe doesn't believe it's Billie and Christy. Behind a door they enter a room with a glowing disc but they can't see it. They emerge and find a group of demons led by Christy, who calls them off. The Halliwells back down and leave, and then Christy complains about the demon leader Creo's presence, telling them to wait…until they're ready.
Piper and Paige are comparing notes on how being a Charmed One affects marriage when they're called in by Phoebe. They give her grief about being in love with Coop before Phoebe reveals she has compiled a list of their prior magical allies that they can call on this time. Billie is working on a ritual to depower the Halliwells and Christy says it's pointless, but Billie is clearly reluctant. Christy reveals the Halliwells were here and Billie starts to come around.
Paige goes to visit the leprechauns to ask for a favor and they've already heard about the brewing storm but are reluctant to help. Paige eventually flatters them into helping. Coop teleports in to the attic and almost gets banished by a surprised Phoebe. He reveals he has someone for her and she finally admits she wants him despite the rules forbidding it, and they kiss. Piper interrupts and Coop makes a quick exit. Phoebe has identified Creo and Piper has a truth spell to make him talk once he gets away from Magic School.
Christy shows Billie the room with the disc and a figure appears – her imaginary friend Dumaine. He claims they've been given power to keep the Halliwells in check and her and Christy are the only ones who can do it. He shows them a vision of the future with Wyatt and Chris in the future, but Billie can't bring herself to go along.
After the sisters leave, the Triad appears before Dumaine and tells him the plan he created must succeed, and he's been working for fifteen years to bring their plan to fruition. If the plan doesn't succeed, the Triad can't return and Dumaine can't join with them. The Triad senses someone approaching and both they and Dumaine fade away as the leprechauns sneak in. They can't see the disc either and cast a spell using their gold to reveal the unseen, but the disc bursts into flame and smoke and the leprechauns have to retreat without their gold. Dumaine decides they can use the leprechauns to convince Billie and summons Creo.
Billie and Christy are fighting when the demons burst in to attack the leprechauns. Dumaine (who has staged the whole thing) advises Christy to call the demons off and Creo obeys. Christy then appeals to the leprechauns who admit the Charmed Ones sent them.
Piper and Phoebe are discussing the matter and Piper is comfortable with having to kill them if necessary, while Phoebe has her doubts. Phoebe is scrying for Creo and gets a trace and they head out. The leprechauns wonder why the Charmed Ones think Billie and Christy are evil and they planned to vanquish the ultimate power. Dumaine carefully maneuvers them into admitting the Charmed Ones are using them as cannon fodder.
In a deserted alleyway, Creo and his minions are lurking and complaining when the Paige and Phoebe arrive. Paige orbs them into a garbage dump and then Phoebe uses the truth potion. Rather then speak the name of their master, they immolate themselves.
Back at the manor, Paige summons the leprechauns who give them grief and leave in a huff. The Halliwells starts to figure out what's going on and go to warn the magic community while Paige tries to talk with the leprechauns again. Dumaine assures the Triad that Billie needs only a little more convincing and they need to create a situation distracting the Halliwells and putting the magic community under threat. Using Billie's notes, Dumaine plans to summon the witch doctor who opposed them in the past.
Paige meets with the leprechauns and tries to convince them, but as she starts to get somewhere she's hit with some kind of spell and forgets what they're talking about and orbs off. Dumaine then uses Billie's notes to hit Phoebe with a lust spell and Piper with their grandmother's ring that turned Phoebe into a perfect housewife.
The magic community has assembled and the various groups argue over the Charmed Ones' perceived actions. They're interrupted by a demon attack that kill many and send the rest into a panic. The head leprechaun goes to get Paige but she's meditating atop the Golden Gate Bridge and sends him away. Just afterward the spell breaks and she begins to realize what happened. One of the dryads go to the manor but find Phoebe and Coop together, and then a demon arrives and the dryad escapes, but Phoebe realizes something is up.
Piper is cleaning when a fairy arrives to ask her for help, and a demon arrives to destroy it. The demon leaves and Piper's spell breaks. The head leprechaun goes to Magic School and Billie offers their help. The sisters regroup and figure out what's going on and assume Billie is responsible. The remainder of the magic community is up in the attic where they reveal that Billie and Christy already saved them. Billie and Christy step in and summon a fireball, and the Halliwells just manage to grab the album and orb out for Magic School, but get deflected away by a protection spell into the underworld.
Dumaine informs the Triad the Halliwells are on the run but he figures they'll attack Billie and Christy and all of the witches will be destroyed and the Triad can return.