The Forbidden Tower
The Forbidden Tower is a science fantasy novel by American writer Marion Zimmer Bradley, part of her Darkover series. Originally published by DAW Books (No. 256) in 1977, it is the sequel to The Spell Sword and is followed by The Bloody Sun. The major characters also appear in Thendara House and City of Sorcery.
This book is set approximately forty years after the events in the book Rediscovery. The Hilary Castamir stories in the collection Marion Zimmer Bradley's Darkover precede the events in The Forbidden Tower by about ten years.
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