Pobby and Dingan live in the opal capitol of Australia. They are friends with Kellyanne Williamson, the daughter of a miner - but only Kellyanne can see them. Pobby and Dingan are imaginary. Kellyanne's brother Ashmol, thinks his sister should grow up and stop being such a fruit-loop - until the day when Pobby and Dingan disappear, the same day that his father is accused of ratting, the worst sin an opal miner can commit.

As Kellyanne, grief-stricken, begins to fade away, Ashmol recruits the whole town in the search for Pobby and Dingan. In the end, however, he discovers that only he can find them, and he can only find them if he too begins to believe they are real. Opal Dream is an enchanting, funny and profoundly moving story.