Shantih, Jinny's chestnut Arab mare, has to wait in a field until Jinny arrives back on the school bus and rides her back to Finmory. Fit and bored, she jumps out. What, thinks Jinny, can she do to keep her horse interested?

And what can she do to try and save the Wilton museum, where she painted the mural of the glorious golden horses? It is to be demolished.

Miss Tuke tells Jinny all about a long distance ride, ideally suited to Shantih, for Arabs are the best type of horse for endurance. But Clare Burnley, Jinny's nemesis from a few summers ago, is back in the area, with a brand new horse bought just to take part in the endurance event. Clare is just as dismissive of Jinny as she was when they first met; just as rude about Shantih.

Jinny is determined to show Clare just how good Shantih is.

And in the end, she finds a way to save the golden horses.