Three children on a holiday in Cornwall find an ancient manuscript which sends them on a dangerous quest for a grail that would reveal the true story of King Arthur and that entraps them in the eternal battle between the forces of the Light and the forces of the Dark.Vacationing in a seaside village in Cornwall, three children stumble upon a brittle old map showing the location of a magical relic of Arthurian days, leading them into a high-pitched battle of good and evil

- Fantasy fiction.

When the three Drew children (Simon, Jane, and Barney) go to Cornwall for a summer holiday with their parents and their Great Uncle Merry, they are drawn into a race to locate an ancient treasure after finding a mysterious old map that appears to have been created by King Arthur. Their search places them in great danger, caught up in the ongoing battle between the Light and the Dark.

Over Sea, Under Stone is probably my favorite book in Susan Cooper's expertly crafted Dark Is Rising Sequence. Perhaps it is because I have always enjoyed reading the Arthurian legends to which this book is so cleverly connected. As all of the books in the Dark Is Rising Sequence do, Over Sea, Under Stone takes place withing the framework of England as a land full of ancient customs and magic: the England of Stonehenge, Tintagel, and traditional dances / parades such as the Floral Dance mentioned in this novel. Susan Cooper brings these legends to life in the context of a modern day mystery / adventure. The pace of the novel is very like that of one of Alfred Hitchcock's movies: deliberate with a building sense of the sinister. Like Hitchcock's films, it is filled with characters who may or may not be what they appear. Much of the action is related to figuring out the truth about these characters and their intentions, but in the end it is very clear who is fighting for good and who is fighting for evil. The denouement occurs in a fast-paced series of scenes at the end of the novel. While suspenseful, the plot of Over Sea, Under Stone is not frightening; it is exciting and the book is hard to put down.

Margery Gill's pen and ink sketches are scattered throughout the book. She is particularly adept at portraying the setting of the novel and the children's response to the various events that occur during their search for the grail. Whether the Drew children are enjoying the Cornish sun, feeling threatened and uncertain, or involved in an exciting chase, Gill's sketches capture their state of mind at that particular point in the story. The illustrations support the text while adding another dimension by helping a reader who has never been to Cornwall to visualize the rocky Cornish coast that is such an integral part of the storyline.

1. Learn some of the Arthurian legends. Are there other places in England that are connected to these legends? 2. Legend has it that Tintagel in Cornwall is the site of King Arthur's castle. (Merlin's cave is said to be below the headland on which the ruins of the castle sit. It is only accessible at low tide.) 3. Look at a map of Cornwall. The names of many of the towns begin with the letters "tre". Find out why. 4. Cornwall had its own ancient language that was revived in the early 20th century. Could the instructions on the map of Kemare Head have been written in Cornish? What can you find out about the Cornish language?

Other books in the Dark Is Rising Sequence (in order after Over Sea, Under Stone which is the first) are: 2. The Dark Is Rising 3. Greenwitch 4. The Grey King and 5. The Silver On The Tree.

Legends of King Arthur: The Light Beyond The Forest by Rosemary Sutcliff, King Arthur and His Knights of the Round Table by Roger Lancelyn Green, King Arthur and the Round Table by Geraldine McCaughrean, and Sir Gawain and the Green Knight by Michael Morpurgo. Other Legends tied to Cornwall: The Mousehole Cat by Antonia Barber (This book takes place in a small town near Penzance. It is a picture book but the story can be enjoyed by readers of all ages.)

Susan Cooper (1935 - )