Holly feels rejected. Her cool, remote mother has dumped the thirteen-year-old girl on an aunt and uncle she barely knows, at a farm in southern England. Her mother and father said they needed some time alone to discuss things. Holly knows what that means: the D word. To make matters worse, her grumpy cousin Frederick pesters her incessantly. There's only one relief from her predicament: her music. In a fit of defiance and desire to escape, Holly takes her recorder to her aunt and uncle's old barn to practice. But the notes of her recorder set off a mysterious and compelling hum from the back of the building.Perhaps she shouldn't have gone to investigate the sounds. Maybe she shouldn't have moved the pile of broken-down farm implements that blocked her path. But how else was she going to get that ancient-looking door open? Besides, somehow Holly couldn't help herself.Before she understands what's happening, she finds herself transported to 700 B.C., when Iron Age people were settling in the region of Stonehenge. Not only that, but they seem to think she's some kind of warrior come to save them from their enemies, the marauding Celts. Holly doesn't have a clue about what all this means, and her problems between her parents are enough to handle at the moment. She returns mysteriously to her own time determined to forget the whole terrifying experience.