A new post box is being opened in Biggleton, and Ava the Postie is practising a special dance to celebrate. But Ava is nervous and keeps forgetting her dance steps. Dolly the Popstar lends Ava her music box to help her practice, but that doesn’t work. Amelia the Scientist suggests she practices beside the post box, but Ava still can’t remember her steps. Finally, Road Sweeper Keven thinks of an unusual way for Ava to remember her steps, so everyone can celebrate the new post box.