The chapter begins after Marie-Laure has brought back her first loaf of bread from the bakery and presented it to Etienne. Etienne opens the loaf, and finds a small scroll inside. He tries to understand what the scroll says—it’s printed with numbers in no clear pattern. Etienne carves a fake panel on the back of the wardrobe on the sixth floor—this allows him to enter the radio room whenever he needs to do so.
In this important expository section, Doerr establishes the pattern of resistance that Marie-Laure and Etienne use: they spend their days picking up source codes for the French, and then transmitting them over the radio. In this way Etienne is able to reach thousands of resistance fighters—accomplishing a great deal, contrary what he claimed earlier to Manec.
In the radio room, Etienne reads off the numbers on the scroll, and tells Marie-Laure that the information has been spread to Paris, and to England. He remembers what Madame Manec said about the frog in the pot of water, and tells Marie-Laure that he’s not sure who the “frog” was in Manec’s analogy: Manec herself, or the Germans.
Here, Doerr scrambles his own analogy and acknowledges its ambiguity. The frog in the pot of water could be the Germans, or else the French trying to ignore injustice (as discussed earlier), but it could also be Manec herself—either trying to avoid being “boiled,” or slowly conditioning herself to acts that may result in the deaths of innocents (the French Resistance was sometimes criticized for killing German civilians, rather than soldiers). Essentially the analogy means that humans can accept or adjust to anything, provided the transition is slow or unnoticeable enough.