The Biggs family vacations in Scotland, and instead of a tourist trap, prefer to stay in a remote location. When an idyllic cottage overlooking Loch Meradoon is available at the height of the season, they believe it will be perfect for their first visit to the Highlands. Assured of a quaint cottage surrounded by beautiful views, it seems a dream to be near both the loch and the romantic, ruined Castle of Meradoon.

One misty morning the children, Emma and Thomas, decide to explore the eerie castle. Thomas, two years younger than Emma, isnt thrilled about climbing around the musty, smelly, ugly, old ruin. But Emma is keen to do something different and exciting on this vacation, something theyd never do at home. When they get inside, they encounter something beyond their wildest imaginings. They are immediately propelled into a series of adventures: exciting, mysterious, puzzling, and even frightening.

As this memorable vacation draws to a close, the children receive a special gift, a gift so unique it comes with life-changing consequences.