Because of their notable achievements, Rist and Rusk have earned their new "man-names" of Thist and Thusk. They each have earned important positions in the Sisterdom of ShadowFall, but find themselves having to import and train their countrymen to help defend the Princess of ShadowFall against an invasion from the army of a new Mother and her treacherous chief priest. They prevail, but at a cost to themselves and others. Meanwhile, on the Moon, a strange child named Mien falls into a tunnel being melted by the tunneling engineers of Community. Through ancient technology used solely by the Mother of Motherland, Thist accidentally makes contact with Mien, a meeting that affects the battle for ShadowFall's survival.

From their primitive, mist-bound homeland at the foot of receding glaciers, to warmer and more civilized lands downriver and below, twin diminutive "bird-rider" warriors venture southward, taking with them the seeds of revelation and revolution. On the Moon, human colonies have likewise evolved. Those two worlds after the next Ice Age are very different places from today, but human emotions, personalities, and reactions remain unchanged.

The Thaw Trilogy is a tale of future conflicts—the clash of ancient institutions and ancient technologies on an unfamiliar Earth, and remnant human colonies on Earth's Moon.

The Thaw Trilogy, incorporates three stories that first appeared in Analog—"Thaw" (July/August 2013), "Flow" (November 2014 - Hugo nominated), and "Fall" (July/August 2016).

At the publisher's request, this title is sold without DRM (Digital Rights Management).