Von Rumpel tries to track down the designer of the safe from the Natural History Museum. He finds evidence that the safe’s designer stayed in an apartment nearby. He talks with the landlady, who tells him that the man left his apartment in the summer of 1940. She explains that checks for rent are mailed to her every month—the Natural History Museum still pays rent on the man’s apartment, even though he’s never there. The landlady also mentions that the man had a blind daughter. Inside the apartment, von Rumpel finds tiny models, bottles of glue, and small saws.
We can see von Rumpel getting closer and closer to tracking down Daniel LeBlanc, who, it’s now made explicitly clear, is the possessor of the real diamond. It’s poignant that von Rumpel doesn’t see the model of the city for what it is—a reflection of Daniel’s love for Marie-Laure.
Von Rumpel inspects the large model of Paris he sees in the middle of Daniel’s apartment. As he stares more closely at the model, he remembers the intricate designs of the safe that held the first false version of the Sea of Flames. Exhilarated, von Rumpel seizes the tiny model of the apartment house in which he’s standing. He throws it on the ground and stomps it open with his shoe.
Von Rumpel doesn’t even try to understand why Daniel would build a model of the city—he assumes that the house is a treasure chest for the diamond. Instead of using his hands to solve the puzzle and open the house, as Marie-Laure would, von Rumpel simply stomps on it. This is a telling sign of von Rumpel’s bluntness, violence, and ravenous greed.