Peter Van Zandt, a professor of archaeology at a small liberal arts school north of Boston, makes a discovery that could boost his career ... or destroy him. Mourning the death of his beautiful wife, Linda, and attempting to be a good father to his six-year-old son, Andy, Peter is hired to excavate a potentially remarkable early American archaeological site on an island in Boston Harbor where a new casino resort is to be built. Workers have unearthed the remains of a peculiar stone edifice, perhaps Celtic in origin, but Peter and his team of young volunteers have little time to determine its significance before construction begins. As they uncover a circle of stones eerily reminiscent of Stonehenge, Peter finds himself assaulted by disturbing visions of his young son with his throat slashed, the burning of an accused witch at a stake, and a woman who seems to be his wife calling him from beyond. Peter leads the excavation at a frantic pace, discovering a skeleton that could be the witch from his dreams. Soon the lines between this world and the next begin to blur, until finally Peter is convinced that it is his wife, Linda, who beckons him from the other side. He will do anything to be with her again, even if it means making the ultimate sacrifice at the stone circle.