It focuses on the friendship between two young British women in World War II: a spy captured by Nazis in German-occupied France and the pilot who took her there.

A prequel novel, The Pearl Thief, was published in May 2017; it is a mystery involving Code Name Verity's protagonist Julie a year before the war starts.

In the second part of the plot, the story is told from Maddie's point of view, and reveals the events that transpired after the plane crash that left both women in France, and her plan to find Verity and bring her back home.

The New York Times praised it as "a fiendishly plotted mind game of a novel, the kind you have to read twice",[2] and Kirkus Reviews called it a "carefully researched, precisely written tour de force".

[3] Code Name Verity is one of five young adult novels published in 2012 to receive starred reviews in all six trade journals.