Eight-year-old Kellyanne has an idealistic father, Rex, who is one of the many local denizens feverishly mining the landscape for opals; meanwhile, her mother Annie and her 11-year-old brother, Ashmol, are the more 'grounded' members of the family. As much as she loves her parents and big brother, it is Pobby and Dingan who are Kellyanne's most constant companions. As dear friends and loyal playmates, Pobby and Dingan are indispensable. They are also invisible--but when they are suddenly not to be found by Kellyanne, the worried girl falls ill. As Ashmol takes it upon himself to rally the Williamson family and the community around his sister and her missing friends, everyone discovers what Kellyanne has long known; that you don't necessarily have to see in order to believe.