Kay Lansing, who has grown up in Englewood, New Jersey, is the daughter of the landscaper to the wealthy and powerful Carrington family. Their mansion--a historic 17th-century manor house transported stone by stone from Wales in...

Kay Lansing, who has grown up in Englewood, New Jersey, is the daughter of the landscaper to the wealthy and powerful Carrington family. Their mansion--a historic 17th-century manor house transported stone by stone from Wales in 1848--has a hidden chapel. One day, accompanying her father to work, six-year-old Kay succumbs to curiosity and sneaks into the chapel. There, she overhears a quarrel between a man and a woman who is demanding money from him. When she says that this will be the last time, his caustic response is: "I heard that song before."

That same evening, the Carrington's hold a formal dinner dance after which Peter Carrington, a student at Princeton, drives home Susan Althorp, the eighteen-year-old daughter of neighbors. While her parents hear her come in, she is not in her room the next morning and is never seen or heard from again.

Throughout the years, a cloud of suspicion hangs over Peter Carrington. At age forty-two, head of the family business empire, he is still "a person of interest" in the eyes of the police, not only for Susan Althorp's disappearance but also for the subsequent drowning death of his own pregnant wife in their swimming pool.

Kay, now living in New York and working as a librarian in Englewood, goes to see Peter. Kay sees Peter as maligned and misunderstood, and she soon falls in love with him. Over the objections of her beloved grandmother, she marries him. To her dismay, she soon finds that he is a sleepwalker whose nocturnal wanderings draw him to the spot at the pool where his wife met her end.

Kay develops gnawing doubts about her husband. She believes that the key to the truth about his guilt or innocence lies in the scene she witnessed as a child in the chapel and knows she must learn the identity of the man and woman who quarreled there that day. What Kay does not know is that uncovering what lies behind these memories may put her own life in danger...