The arrival of Allied troops that Madame Ruelle refers to likely is D-Day, June 6, 1944; in her conversation with Marie-Laure that occurs during the final days of May 1944, she notes the Allies will arrive “Within the week.” Her coded statement that “the mermaids have bleached hair” appears to be a reference to the Allies’ amphibious landings on the Normandy beaches.
While Werner and his crew are traveling to Saint-Malo, they make a stop along the French coastline. Werner is so enchanted by the sight of the ocean that he unwittingly wanders into a minefield. This scene signals two things. First, Werner’s fascination with the ocean mirrors Marie-Laure’s; although the two have never met, in a sense they are kindred spirits because both of them are enchanted by the beauty of the world around them. Second, Werner’s oblivious journey into the minefield foreshadows his death, which will happen in the same fashion just a few weeks later.
The theme of seemingly insignificant things having significant power emerges when one of the Nazi soldiers debriefing Werner’s team on Etienne’s broadcast mentions that these broadcasts end with music, the meaning of which is unclear. Although the music seems meaningless, it has great meaning both to Werner and to Etienne. To Werner, the “Clair de Lune” is one of the signals that this broadcaster is the same one from his youth. For Etienne, the choice to play music despite the greater risk of being caught is an act of hopeful defiance.