In "Over Sea, Under Stone," Susan Cooper weaves a tale that connects the present with the legendary past of King Arthur and his world, which was filled with magic and light before darkness enveloped it. The story evokes a sense of nostalgia and a desire to reclaim the ideals of heroism and chivalry that Arthur's legend embodies.

The quote, "In the name of King Arthur, and of the old world before the dark came," serves as a powerful reminder of the struggles between light and dark. It signifies hope and the timeless battle against evil, encouraging characters to draw inspiration from the noble legacy of King Arthur as they navigate their own challenges.