The Family D'Alembert series is a set of science fiction

Science fiction

Science fiction is a genre of fiction dealing with imaginary but more or less plausible content such as future settings, futuristic science and technology, space travel, aliens, and paranormal abilities...

 novels by Stephen Goldin

Stephen Goldin

Stephen Charles Goldin is an American science fiction and fantasy author.-Biography:Goldin was born in in Philadelphia, Pennsylvania....

, the first of which was expanded from a novella by E. E. "Doc" Smith.

Plot

Jules and Yvette D'Alembert are a brother and sister team of aerialists in the D'Alembert family Circus of the Empire and also work as agents in SOTE, "The Service of The Empire", the imperial intelligence agency.

Series

The series comprises the following books:

1. Imperial Stars
   Imperial Stars
   The Imperial Stars is a science fiction novel by Stephen Goldin expanded from a novella by E. E. "Doc" Smith. It is the first in a series of ten Family D'Alembert novels set in a future where humankind has expanded to the stars but reverted to an old-style feudal system of government in an advanced...
   
   (1976)
2. Stranglers' Moon
   Stranglers' Moon
   Stranglers' Moon is a 1976 science fiction novel written by Stephen Goldin, the second book in the Family D'Alembert series, the first of which was expanded by Goldin from a novella by E.E. “Doc” Smith.-Plot introduction:...
   
   (1976)
3. The Clockwork Traitor (1976)
4. Getaway World (1977)
5. Appointment at Bloodstar, also known as The Bloodstar Conspiracy (1978)
6. The Purity Plot (1978)
7. Planet of Treachery (1981)
8. Eclipsing Binaries (1983)
9. The Omicron Invasion (1984)
10. Revolt of the Galaxy (1985)