Zoe, Jennifer and Nadia are three women with nothing in common except the letters they receive, each one full of intimate details about every aspect of their lives - from the clothes they wear to the way they act when they think they're alone. And if that isn't terrifying enough, the letters also contain a shocking promise: that soon each life will come to a sudden, violent end. Can Zoe, Jennifer and Nadia discover who their tormentor is? And if so, will any of them live long enough to do anything about it?