Traitor's Sun (Daw Book Collectors, 1109) Hardcover – January 1, 1999 by Marion Zimmer Bradley 
Book 9 of 11: Darkover
 
It has been fifteen years since Marguerida Alton returned to Darkover. Fifteen years since she discovered the terrifying powers of her special laran, met and fell in love with Mikhail Lanart-Hastur, heir designate to the throne of Darkover, and journeyed back in time to the Ages of Chaos to answer the call of a long-dead Keeper.
Now Marguerida's life is more settled. As the seconds-in-command to the aging Regent, Regis Hastur, and his consort Linnea, life in Comyn Castle for Marguerida and Mikhail is far from serene.
But the real root of the current tensions on Darkover has more to do with the Terran Federation than anything internal to Darkover. The once pleasant relationship between Darkover's ruling families and the Terran envoys to Darkover has been shattered, primarily due to the machinations of Lyle Belfontaine, the corrupt and ambitious Station Chief at Federation Headquaters.
When the sudden death of Regis Hastur leaves Comyn Council in turmoil, Belfontaine sees an opportunity to wrest by force what he could not gain through diplomacy, and plans a violent takeover on Darkover.
Can Mikhail and Marguerida, new Regent and consort on Darkover, face the might of Terran weapons with only their combined telepathic laran powers?
 
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