John has been away from Bartlesville for 12 years; all his friends have gone and his childhood sweetheart dumped him when he left for college. When he returns, he discovers that the so-called "house" is actually a 52-room mansion on a high hill overlooking the city. Being a college professor of limited means, John has no idea what he will do with a huge estate; his salary would barely cover the utility bills. To John, Ravenhurst Manor is a white elephant—a money pit.

Out of curiosity, he looks up his childhood sweetheart Brandy; she runs the Emerald Bar, which she had inherited from her father, a retired sea captain. Brandy is thrilled to see John; neither of them are attached and they renew their romance.

Together, they begin to explore Ravenhurst manor. From the beginning, they have a strange feeling about the house—although it has been closed up for nine years, there is not a speck of dust or dirt anywhere. John finds a diesel generator; he gets it started and they have electrical power, so they decide to spend the night in the manor house. During the night they see a naked girl with pale skin and snow-white hair fleeing down a staircase; Brandy thinks she's a ghost, John is not so sure.

A man claiming to be a lawyer representing an anonymous client shows up and offers John three million dollars cash for Ravenhurst Manor and all its contents, provided they leave immediately. Brandy is suspicious and talks John into refusing until they can explore the rest of the house. But explore as they may, they can find nothing which would be worth that much cash.

Mysterious things begin to happen: the three-acre lawn has not been mowed for nine years, the swimming pool is full of leaves and trash, and there is no hot water. After discussing this sorry state of affairs, they retire for the night. When they awaken the next morning, the lawn has been mowed, the pool is full of fresh, clean water, and there is plenty of hot water. Something else is also happening: both of them notice that their sexual encounters are abnormally frequent and powerful—they are literally unable to keep their hands off each other, and they devote much of their time to making love and not on the business at hand. Although this is a very pleasurable experience, they both realize that something is controlling them.

As they explore the manor and grounds, they begin to learn about the Ravenhurst family. Old Charles had three beautiful teenage daughters; all were dead. His last wife Helen had been brutally murdered; her body had been found floating in the fountain in the front courtyard. Two of the daughters had died on the estate grounds, and the third, Sarah, had been lost overboard in the Mediterranean. Charles himself had gone insane and jumped from the roof of the manor. Helen’s murderer had never been found; John and Brandy resolve to find the culprit.

The lawyer returns and offers ten million dollars for the estate but won’t reveal the name of his client. John and Brandy again refuse him, believing that there must be something in or around the manor which is worth a fortune. They continue to explore and find a locked wall safe behind Helen’s portrait. While they are exploring the library, a slip of paper falls out of a book; this proves to be the combination. Inside the safe is a metal object resembling a snowflake.

John and Brandy discover the Ravenhurst family crypt in the woods by the lake. On Helen’s sarcophagus is a depression which matches the snowflake. Brandy puts the snowflake in the depression and a floor slab descends. They ride the slab down and discover a tunnel which leads back under the manor house to a strange room filled with mysterious electronic equipment, none of which is recognizable, and none of which seems to be functional. It is obvious that this control room is the secret of Ravenhurst Manor, but what is its function?

The lawyer’s client becomes desperate; he hires thugs to kidnap Brandy; she narrowly escapes. As they relax on the balcony of the manor, they are shot at and again they barely escape. To protect themselves, they hire two security guards to patrol Ravenhurst Estate. The guards are two young girls who were formerly Air Police; the house’s power becomes apparent when they become sexually obsessed with John, as do several of Brandy’s female friends who come to visit.

Having failed in his attempt to kidnap Brandy, the mysterious client hires Robert Kane, a modern-day Moriarty. He sends his young teenage ward Candy to infiltrate the manor and endear herself to John. This turns out to be extremely easy due to the house’s control over its occupants’ libido. During one of their sexual encounters, John discovers that Candy has a tattoo on the small of her back which matches the snowflake. He and Brandy take her to the secret room; she sits in the control chair and the room comes to life; somehow it has interfaced with the tattoo, and they realize that Candy is somehow connected to Ravenhurst Manor and the secret control room.

Candy has fallen in love with John; she refuses to leave Ravenhurst Manor. Her guardian Robert is outraged and sends a group of mercenaries to kill everyone in the house, including Candy. They succeed in killing one of the security girls. The leader of the mercenaries abducts Candy and strangles her; John intercedes and kills him but it is too late for Candy. Or so he thinks—a mysterious girl with pale skin and snow-white hair emerges from the shadows and takes Candy’s body to the control room. There Candy is revived, and the mystery girl tells her story.

She is Sarah, the youngest of Charles’s daughters. Her death in the Mediterranean was staged; she has been "sleeping" in a secret alcove adjacent to the control room, awaiting the arrival of John and Candy. Sarah explains that Ravenhurst Manor is just one of a group of residences scattered around the world. They were built by a group of off-world creatures as havens for the offspring of its occupants— occupants such as John, Candy and Sarah, who have been genetically engineered to be the progenitors of a new order of human beings, the next stage in human evolution. The safe haven is necessary because of the powers these new humans will possess. At some point in the not-so-distant future, this new race of humans will use these powers to help defend the Earth in a galaxy-wide battle between the forces of good and evil.

An ongoing side investigation of Helen’s murder has taken place throughout the book; John and Brandy discover that she and two of her daughters had been murdered by the man who delivers fuel for the diesel generator. Robert Kane and his mercenaries are arrested for the murder of the security guard. The client who hired them is revealed as the executor of Charles’s will, who was aware of the control room but not its function, and he mysteriously plunges to his death from the balcony of his office.

And as for Brandy, Candy and Sarah, new life stirs within their wombs. Brandy’s child will not be of the new order, but she doesn’t care, nor does John, for they are now husband and wife and their love knows no bounds. The world is safe for the moment, but John and Brandy knows in their hearts that it won't always be that way.