Original title was The Mixed Men. A fix-up: source stories are "Concealment", "The Storm", and "The Mixed Men" - all from Astounding - from the early to mid Forties. Chapters 1-7 were original to the 1952 Gnome Press hardcover, but have also been reprinted as "Lost: Fifty Suns."

The Lady Gloria Laurr, Grand Captain of the Imperial Battleship Star Cluster, is on a mission searching for certain inhabited planets in the Greater Magellanic Cloud. The inhabitants of these planets know of the search and expected it for centuries, but refuse to reveal their location. What is their secret? Why are they hiding?