Contains spoilers for this episode and earlier episodes.
Dipper and Mabel visit the Tent of Telepathy despite Stan's hostility toward its star, the child psychic Gideon Gleeful. Mabel enjoys Gideon's enthusiasm for makeovers and sparkly things, believing that she has found a new friend. Gideon wants a girlfriend instead. He surrounds his requests with gifts and public declarations, making Mabel feel too guilty to refuse. One reluctant date becomes another, while Stan welcomes a business arrangement with Gideon's father, Bud. Dipper urges Mabel to say what she wants. When she cannot bring herself to end the unwanted romance, he offers to deliver the message for her.
Gideon acts calm when Dipper explains the breakup, but privately decides that her brother has turned Mabel against him. He uses Toby Determined to lure Dipper into a trap and reveals that his amulet can move objects without touching them. Gideon attacks him, refusing to accept that Mabel made her own choice. Meanwhile, Mabel realizes that she needs to speak directly and goes to find Gideon. Seeing him threaten Dipper ends any wish to preserve their friendship. She takes the amulet, rescues her brother, and tells Gideon she will never date him. Dipper destroys the source of Gideon's powers. Gideon vows revenge on the Pines family, and the closing scene reveals that he possesses another numbered journal.