Dark Dance

"Dark Dance" (1992) is the first novel in The Blood Opera Sequence by Tanith Lee.

Rachaela is a young woman who lives alone in London, working in a meaningless job. She is apparently without friends or family until one day, she is invited to join the family of the father she has never known.

This family, known as the Scarabae, lives together in a large and luxurious but secluded house in the countryside. Aside from Rachaela, all of them appear to be old and eccentric until the day she first meets her father, Adamus. Adamus had fathered her on a woman outside the family many years ago, but he still appears to be a young man close to Rachaela's own age.

Since Rachaela's birth had broken a long pattern of sterility among the Scarabae, the family decides to continue the breeding plan by coupling her to Adamus. The resulting daughter, Ruth, is also intended for the same fate, but Ruth's unexpected madness brings death among the Scarabae and burns their ancient house around them.

Ruth flees to wreak havoc in the normal world; those events and the fate of the surviving Scarabae are told in the sequel, Personal Darkness.