Marie-Laure lives in Paris near the Museum of Natural History, where her father works. When she is twelve, the Nazis occupy Paris and father and daughter flee to the walled citadel of Saint-Malo. Werner Pfennig, an orphan, becomes an expert at building and fixing crucial new instruments to track down the resistance. Deftly interweaving the lives of Marie-Laure and Werner, Doerr illuminates the ways, against all odds, people try to be good to one another.