The discovery of an ancient relic belonging to the original settlers of Pern marked an enormous change for the people of Pern.
AIVAS, an artificially intelligent computer, brought with it the knowledge of how to rid the world of Thread forever. But to carry out its plan, the Pernese would have to learn what the original settlers knew and they don't have long to regain knowledge lost over centuries..
It is up to the dragons and their riders to carry out the difficult and dangerous task - and there is a special role for Lord Jaxom of Ruatha and his white dragon Ruth.
Chronicles of Pern: First Fall
How was the original survey of Pern carried out?
Why did nobody check on the Pern colony?
When were the extra Weyrs established - and when did the Lords of Ruatha take Hold?
Chronicles of Pern is a collection of short stories that answers all these questions and more.
Nobody believes young Jayge when he says the shipfish that saved his life spoke to him. But as Jayge grows up, he grows more and more determined that the shipfish - or dolphins - can communicate.
He is not the only one to think the same but it is not until the discovery of AIVAS, an artificially intelligent computer belonging to the original settlers, that Jayge is proved right.
But can he persuade the others that the dolphins have a contribution to make to Pern?
(in The Girl Who Heard Dragons)
Aramina's ability to hear all the dragons could be considered an asset.
But when it brings her and her family to the attention of Thella, the ruthless Lady Holdless, it's an ability she wishes she didn't possess.
At the start of the Second Pass of the Red Star, Pern's dragons and riders are preparing once again to take to the skies to flame the deadly Thread.
But there are those on Pern who do not believe the Thread will come and who refuse to ready their land and people - and who are violating the settlers' Charter in other, more vile ways.
It is up to the newly-established Harper Hall to persuade Pern to go against the long-established autonomy of Hold, Craft and Weyr, to save those who are suffering.