chunk: One after another, the group either vanishes or being killed and their bodies being found. Kit and Rob put together some clues and realizing that everyone's earlier assumption is wrong; the kinsman of the deckhand injured when they arrived is a red herring. It also turns out that Muffy has a violently insane twin sister named Buffy, who has escaped. In fact, the "Muffy" they have been around since the first night was Buffy, pretending to be Muffy. They discover Muffy's severed head in the basement.