Anne McCaffrey and Elizabeth Ann Scarborough are two of science fiction's favorite authors. Together, they have created the world of Acorna, the unicorn girl. Now, Acorna's children start to have their own adventures. First Warning: Acorna's daughter, Khorii, must contend with an overwhelming legacy to forge a path of her own. A simple journey to visit her relatives turns into a race against time when Khorii comes across a derelict spacecraft drifting in space, its crew dead in their seats. But this gruesome discovery is only a dread harbinger — a deadly plague is spreading across the universe and not even the healing powers of the Linyaari can slow its horrific advance. Khorii, one of the few unaffected by the outbreak, must find a cure before the disease consumes all in its path — including her beloved parents.

Although she has made peace with her Linyaari heritage, Acorna knows that only by returning to the frozen stillness of space will she ever feel truly at home.

Every two hundred years or so, shimmering Threads fall from space, raining death and black ruin on Pern. The great dragons of Pern hurl themselves through the beleagured skies, flaming tongues of fire to destroy deadly Thread and save the Planet. But it was not Threadfall that made young Menolly unhappy. It was her father who betrayed her ambition to be a Harper, who thwarted her love of music. Menolly had no choice but to run away. When, suddenly, she came upon a group of fire lizards, wild and smaller relatives of the fire-breathing dragons, she let her music swirl around them. She taught nine of them to sing. Suddenly Menolly was no longer alone — she was Mistress of Music and Ward of the dazzling fire dragons.