THE FORBIDDEN TOWER [dkvr]
DAW (#256; UJ1323) 1st printing September 1977 paperback. Cover by Richard Hescox, 364 pages,$1.95 cover price. Condition is Fine: tight and square with flat spine; age tanning is mild and uniform (darker on insides of covers.) No stamps, marks or writing - a very clean copy that looks unread.
The Forbidden Tower - a direct sequel to The Spell Sword, involving most of the same characters, beginning less than a year after the events of that novel.
The 4 main players from the previous novel: Andrew Carr, a Terran; Callista, the girl of his dreams (raised to be a Keeper in one of the Towers where the Darkovans used their matrix technology); her twin sister the Lady Ellemir; and her fiancee Damon Ridenow - all had been bound together when they had to rescue Callista after she was abducted by Catmen. Damon had been told he was strong enough to be a Keeper if men were permitted that station. The course of events leads this group to decide that they could and should create their own Circle - forming their own Tower in defiance of repressive teachings.
Another of several Darkover books bound together by the appearance/presence of Leonie Hastur. This was a Hugo-nominee (for "best novel") in 1978.