In a windswept cottage overlooking the sea, Wilder Harlow begins the last book he will ever write.

It is the story of his childhood companions and the killer that stalked their small New England town. Of the body they found, the horror of that discovery echoing down the decades. And of Sky, Wilder's one-time friend, who stole his unfinished memoir and turned it into a lurid bestselling novel, Looking Glass Sound.

This book will be Wilder's revenge on Sky, a man who betrayed his trust and died without ever telling him why. But as he writes, Wilder begins to find notes written in Sky's signature green ink and events in his manuscript start to chime eerily with the present. Is Sky haunting him? Did Wilder have more to do with Sky's death than he admits? And who is the woman drowning in the cove, whom no-one else can see?

No longer able to trust his own eyes, Wilder begins to wonder: is he writing the book, or is the book writing him?