In the novel The Elegance of the Hedgehog, Ozu is a Japanese gentlemen that moves into Renee's apartment building. Renee is fascinated by Japanese art and film, and her "kindred soul" Paloma is also fascinated by all things Japanese, and even speaks Japanese. Both Renee and Paloma have built walls around themselves. Renee pretends to be a simple, uneducated concierge, but she is really an "autodidact" - having taught herself art, music, literature, philosophy, etc. But she does not want anyone to know, so she pretends to be a dolt. This is her wall.
Everyone knows that Paloma is intelligent, but they have no idea HOW intelligent she is. She, too, pretends to be something she is not, and this is her wall. When Ozu appears on the scene, he immediately suspects what is behind each woman's wall and by extending his friendship to each of them, he metaphorically knocks down their walls of protection, exposing them to each other and to himself. They all become friends on a very deep, metaphysical level.
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