In Stirling's alternate world of Marching Through Georgia, the Tories of the American Revolution left the colonies for South Africa and founded a slave-based society that evolved into the Domination of Draka, ruling all of Africa and siding with the Allies in WW II just to gain more land and chattel.
This sequel opens in the 1940s with the Draka reducing Europeans to serfs, as they have already done with Africans and Arabs, and beginning to come into conflict with the U.S. headed by President Marshall. Fred Kustaa, an OSS agent, ventures into Draka territory to bring weapons to Finnish resistance fighters and to smuggle out Professor Ernst Oerbach, a scientist who holds the key to fusion bombs. Kustaa's contact in the latter mission is serf Marya Sokolowska, a captured Polish nun.
Stirling's latest has less military action than its predecessor—though an ambush of Draka forces by Finnish insurgents and a flashback by one of the characters to WW II are limned with vigorous battle scenes—deepening the overall darkness of the author's vision of Draka society. This is a potent, unflinching look at a might-have-been world whose evil both contrasts with and reflects that in our own.