Piper has enrolled Wyatt in a preschool. Wyatt has apparently been talking to himself. Unknown to the Charmed Ones and Leo, he is in fact talking to a demon, Vicus, who has cast a spell on himself so that only Wyatt can see him. Vicus is after Wyatt's teddy bear.
Phoebe talks to one of her professors, who suggests that Wyatt has an imaginary friend.
Piper concocts a spell to try to understand Wyatt, and in the process summons a future Wyatt -- a good Wyatt, quite different from the evil witch-king of "Chris-Crossed". Adult Wyatt walks into baby Wyatt's room and sees Vicus talking to baby Wyatt. Vicus, spooked, shimmers away; in his lair, he realizes that the witch who surprised him was a future Wyatt.
Adult Wyatt identifies Vicus in the Book of Shadows. Several of Vicus's henchmen attack, and with Leo distracted, Vicus appears again to baby Wyatt. Adult Wyatt vanquishes the henchmen, but baby Wyatt gives up his teddy bear to Vicus, who curses it with evil. Leo notices the teddy bear in the hands of an unseen figure, just as adult Wyatt transforms into the evil witch-king, and orbs to Vicus's lair, Darklighter-style.
Paige and Phoebe orb into Vicus's lair. Unable to see Vicus, they throw potions in vain. Wyatt reveals Vicus to them; Paige throws a potion and vanquishes Vicus, but Wyatt is unaffected. He summons dozens of demons, who attack the sisters. He orbs to Magic School and makes off with baby Wyatt. The sisters and Leo suspect that adult Wyatt wants to take baby Wyatt back to the future, so he will be beyond his family's reach. He needs the Book of Shadows to do this, but being evil, he cannot approach the Book. Phoebe suggests setting a trap for him; Leo agrees to be the bait, because he lacks powers and neither Wyatt will see him as a threat.
The two Wyatts orb into the attic. Adult Wyatt tries to persuade baby Wyatt to bring him the Book. Adult Wyatt, though evil, is unwilling to harm Leo. Leo talks baby Wyatt into handing over the teddy bear; the teddy bear glows, the curse is lifted, and adult Wyatt transforms back into the good version.
Piper says a spell to send adult Wyatt back, and now baby Wyatt begins to talk.