As long as the people of Pern could remember, the Holds had protected them from Thread, the deadly silver strands that fell from the sky. In exchange for sanctuary in the huge stone fortresses, the people tithed to their Lord Holders, who in turn...
For generations, the dragonriders had dedicated their lives to fighting Thread, the dreaded spores that periodically rained from the sky to ravage the land. On the backs of their magnificent telepathic dragons they flew to flame the deadly stuff out...