As Sabrina and her aunts get ready for their daily activities, they get a surprise when sunspots cause molecular instability in the Mortal Realm. After Zelda's arm gets attached to Hilda's body and a black hole forms in the kitchen sink, the aunts warn Sabrina to be careful while at school since they don't know how she'll react to the sunspots. At first, Sabrina has mild reactions when dealing with the molecular instability, but when she bumps into Libby, the two girls swap personalities with Sabrina becoming far meaner and more self-centered than Libby, while Libby becomes perkier and sweeter than Sabrina.
The first one to notice the change in Sabrina is Salem, when he finds her studying the self-centered spells in the magic book. To make matters worse, he suggests to her to take over the world, resulting in Sabrina being arrested by the Witches Council where she is set to be turned into a familiar.
Meanwhile, Hilda tries to impress a violin trio in order to secure herself a spot but the molecular instability in the house and then the Other Realm police storming in from the linen closet ruin her chances.
Jill and CeCe reveal that the cheerleaders have always liked Sabrina. but they were frightened of Libby. This may fit into the idea Zelda said in the previous episode that Libby picks on Sabrina as she is jealous of her, so this is maybe why Libby is mean to her as she sees Sabrina as her rival.
Zelda Spellman attempts to reverse the effects of the molecular instability by announcing an incantation in what is supposed to be Latin before Hilda reminds her that mortals are present. "Latin" spell casting would be used again by Duke in Season Four.
