Deciding that Julia, and Lizzie need friends their age, Isabella and Emily decide to enroll them in the Fireside Girls. However, they don't fit in with the other girls, espeicially an older girl named Becky, so together with Thomas, they try to throw a party to impress the other girls. Adrian falls for Becky, and trys to get a dance with her at the party. Isabella and Emily reunite with their old friends from the Fireside Girls, and Phineas and Ferb reunite with their old rival Buford.