More than 90% of the world's opals are mined in Australia, and it is the country's gemstone. They are hidden all over and so many small miners claim a patch of land and start digging with great dreams of finding their own special rainbow. The Williamson family lives in the small, hot, and dusty opal mining town of Coober Pedy in South Australia. Rex (Vince Colosimo) is convinced it's just a matter of time until he finds some gems. His wife Annie (Jacqueline McKenzie), who brings in the family income by working as a supermarket clerk, feels that she's always playing second fiddle to her husband's obsession with striking it rich. Their son Ashmol (Christian Byers) likes tagging along with his dad and respects his enthusiasm. He is a bit tired of his nine-year-old sister Kellyann (Sapphire Boyce), who spends all her time with two imaginary friends named Pobby and Dingan. She pushes them on a set of swings, holds hands with them as she walks the corridors at school, and has afternoon tea with them in a little shed she's set up for them in the back yard.

Her parents don't quite know what to do about her obsession with these imaginary friends. They alternate between playing along with Kellyann by setting two extra plates at the table to insisting that she stop pretending. In town, Annie's boss always gives the little girl two lollypops for Pobby and Dingan. But less sensitive members of Coober Pedy call her a retard.

One day, in an attempt to help her separate from these friends, Rex offers to take them and Ashmol to his mining claim. When they return late that night, Kellyann claims her friends are not in the truck. She throws a fit and insists they go back to the mines to look for them. One of the other miners spots them on his property and threatens them with a gun and the charge that Rex is a "ratter," out to steal opals from his claim, one of the worse things to be called in this community. When this fellow takes him to court charging trespassing, Annie is let go at the store. Meanwhile, Kellyann can't cope without her friends and retreats to her bed with an upset stomach and a fever.

Opal Dream is based on a novella by Ben Rice who also wrote the screenplay for the film. The director is Peter Cattaneo who was at the helm of The Full Monty, another story about wild dreamers and the strange and sometimes wonderful ways community can come about when you least expect it. The central role is that of Ashmol, the brother who at first has very little patience for his sister and her imaginary friends. But when he comes to see how much she misses them and what an important role they have played in her life, he becomes a spiritual warrior willing to anything it takes to make her feel better. One of his best ideas is having her draw them for a poster to put around town; he sees in her sketches the intimate details she knows about their bodies and personalities.

"Imagination is the secret marrow of civilization," says Henry Ward Beecher, a nineteenth-century Protestant minister. "It is the very eye of faith." This faculty feeds our appreciation of the unseen and fuels our dreams of the future. Kellyann's imaginary friends give her life color, detail. and adventure whereas her father's dreams of finding opals give him the energy to face each day with hope. When Ashmol decides to set aside his realism and skepticism about pretending, he begins a project that will help the entire family and even bring some needed solidarity to the community of Coober Pedy. And in doing so, he enlightens us about another important dimension of imagination — the ways in which it can be an instrument of creative love that liberates and gives meaning to all it touches.