Over Sea, Under Stone (book review)

This book is also for the Full Circle Challenge.

Over Sea, Under Stone, by Susan Cooper, is the story of the three Drew children. One holiday in Cornwall, Barney, Simon, and Jane find themselves in a fantastical mansion called the Gray House. The Gray House, which belongs to their uncle Merry Lyon, is full of hidden doors and secret passages. As if by chance, the children stumble upon an old map. It is more special than they know. Their map is the key to finding a grail, a grail that can help them fight the forces of evil known as the Dark. However, there are some people (if you can even call them people) who are determined to find the grail and use it for Dark purposes. The three children have to beware, because the Dark is rising.

I loved the book's sense of adventure, suspense, and fantasy. It's relation to the story of King Arthur made it even more interesting. I'm already reading the next one in the series.