From the front flap of the Gregg Press edition: "Nineteen-year-old Dominic Flandry, fresh out of the Naval Academy and an ensign in the Imperial Naval Flight Corps, has a problem. A spy for the Empire has succeeded in stealing vital information from Merseian files and passing it on to Flandry, information that would reveal the reptilian greenskins' plans to overcome their enemy, Terra. But it is only a mysterious set of numbers, and Flandry has to solve their meaning quickly - to save his neck and that of the Empire - under a serious handicap: he is fleeing from Merseians, who have discovered the burglary, and from his own Terran superiors, who have charged him with high treason, desertion, and kidnapping. In the course of the novel, Flandry romps through furious battles with the Merseians, travels to the underwater dwelling place of the Sea-trolls, where he discovers that the world of the enemy is a beautiful and fascinating one, and learns with bitterness that struggles betweeen great powers often involve a shocking alteration of idealistic principles. Poul Anderson has retreated into the beginnings of Flandry's career to provide another tale of conflict and intrigue between Terrans and other beings who, despite their crocodilian and feline appearances, are very human in their ambitions, feelings, desires, and, to often, treacherous intentions. Flandry has to deal with each of these, using all of his wit, passions, and strength, and the result is a bold-spirited and suspenseful story."
In addition to its stand-alone volume, this title was published in the follow books. It can be rated independently of any volumes containing it.