Pobby and Dingan are invisible. They live in Lightning Ridge, the opal capital of Australia, and are friends with Kellyanne. When Pobby and Dingan suddenly disappear, Kellyanne develops a mysterious illness and her big brother Ashmol, in an uncharacteristic display of affection, recruits the local community to help find these ""missing persons"". This journey becomes a rite of passage, not only for Ashmol but for the whole town. Together they discover that you don't always need to see to believe.