When young artist Peter Davies moves to the mountains of North Wales with his family, he anticipates a quiet and comfortable living capturing the scenery on canvas.   Before he can settle into his new home, though, Peter finds himself experiencing the area through the eyes of a Druid who lived there two thousand years ago.  The Druid's spiritual knowledge sucks Peter into the influence of the Celtic Otherworld, a shadowy realm of magic and powerful gods where myth and reality merge.  As he takes over the Druid's personality, Peter becomes a key figure in both the Ancient British revolt against Roman rule, and in a struggle between good and evil.   Soon he finds himself battling against a force so powerful it threatens to consume both the ancient and modern worlds in an orgy of bloodletting and supernatural worship.