When Chloe visits the Isle of Man for the first time, she is perturbed to find that she 'recognizes' both landscapes and people she has never seen before. Nor can she account for her intuitive knowledge of the Island's history and legends, and as she becomes involved with the masters at her brother's school she comes to realize that one of them has a telepathic hold over her and is able to influence the strange and vivid dreams which have been disturbing her over the last few years.
Old Granny Clegg's obscure warnings add to her uneasiness, and with dawning horror she discovers that the dreams are beginning to come true. But awareness of coming danger affords no protection and eventually, as she knows she must, Chloe finds herself alone in the mist facing an unseen enemy.