Someone in the House

When Anne's friend Kevin asks her to spend the summer at Grayhaven, his parents' new home in Pennsylvania, it seems like the ideal way to complete the book on contemporary literature they have been working on. And Grayhaven, an authentic medieval manor, proves to be nothing short of miraculous. But at the end of three weeks Anne realizes that she and Kevin have not added one new sentence to their book. What is it about this house that is so disturbing?