Jeanne Cross is an ordinary suburban wife and mother with a seemingly "perfect" life when Ali Mather arrives on the scene, breaking all the rules and breaking hearts. Almost against her will, Jeanne is drawn to this powerfully seductive woman, a fascination that soon begins to infect Jeanne's husband as well as their teenage son. Though their friendship seems unlikely and even dangerous to their mutual acquaintances, Ali and Jeanne are connected by deep emotional needs, vulnerabilities, and long-held secrets that Ali has been privately recording in her diary.
The diary also holds the key to something darker. Though she can't prove it, Ali is convinced someone has been entering her house when she is not at home - and not with the usual intentions. What this burglar wants is nothing less than a piece of Ali's soul.