Y/N and Cady are new at North Shore High, where they learn about the school’s cliques and the dangerous popularity of the Plastics. When Y/N meets Rodrick Heffley, they quickly grow close, but things get complicated after they join the Plastics undercover. Trying to compete with Regina—who used to date Rodrick—Y/N changes who they are, drifting away from Cady and their old friends. In the end, Rodrick chooses Y/N over Regina, and they leave all the drama behind, with Cady by their side.