And of course, we'll all stay up till midnight and watch the New Year's Eve ball drop!
— Vivian Garcia-Shapiro
It's New Year's Eve, and Phineas and Ferb build their customized multi-dimensional New Year's Eve ball and drop it to celebrate. At City Hall, Candace goes to a grown up party and makes a resolution to refrain from busting her brothers, but gains a relapse and tries to bust them before the clock hits midnight. Meanwhile, Doofenshmirtz uses a Resolution-Changer-inator in his bowtie to make everyone change their resolution to follow him as their leader.