One of the main themes (or motifs) is that of patriarchy (and rebellion against it), which makes reference to a society in which men make all the rules, thus having authority over women and children. The author sets this up in the first part of the story by demonstrating Jeremy's control of the Sommers household. She also emphasizes it with the creation of Agustín del Valle and his ruthless behavior toward the people who work for him and toward his daughter, Pauline, who tries to defy him.
The author does not merely portray simple patriarchy where women remain under the opressive thumbs of the men around them. Instead she creates conflict. In both cases, with Jeremy and Agustín, the women eventually get their way. No matter how strict the men are, the women do what they have to do in order to pursue their own interests. In parts two and three, Eliza continues to play out the rebellion against patriarchy as she searches for her identity and her independence. In order to do so, she dons men's clothing, stepping into their world and, in essence, competing with them.