The adventures of Frank and Buster, two intrepid young koalas who fly around the Australian outback in their yellow plane, on a special mission to help other creatures in need. Josie gets a tuba but disturbs everyone when she tries to practise. She grows despondent, until Frank suggests that he can fly her to the outback where she can practise alone. This works well, until everyone starts to miss her. When she returns, she gives them all a special performance.