Contains spoilers for this episode and earlier episodes.
Stan hosts a party at the Mystery Shack, and Dipper sees a carefully scheduled opportunity to dance with Wendy. His ticket duties threaten the plan until he discovers that the office copier can produce living duplicates. He creates a double called Tyrone, then more copies to cover chores and remove Robbie from the party. Every Dipper shares the same anxious planning and crush, so what begins as cooperation soon becomes a competition. Elsewhere, Mabel meets Candy and Grenda, whose unusual interests fit her own. When Pacifica Northwest mocks her new friends, Mabel challenges the popular girl for the party crown.
Dipper unexpectedly has a comfortable conversation with Wendy away from the dance floor. He starts to think that talking naturally might work better than following his charts, but the copies insist that he stick to their arrangement. They imprison him and argue over which version deserves the dance. Dipper escapes into a fight among his duplicates, and water destroys most of the paper copies. Tyrone survives long enough to share a drink and admit their mistake before dissolving too. Dipper finally sets the written plan aside and joins Wendy without rehearsing every move. Pacifica wins the crown through a rigged result, but Candy and Grenda stay with Mabel for a sleepover. Her new friendships outlast the competition she lost.