In 'Outlines of Great Novels', one of the essential elements is the setting. It sets the stage for the story, whether it's a specific time period like Victorian England or a fictional place. Another crucial part is the theme. It could be love, power, or the search for identity. These themes are often woven throughout the plot and influence the characters' actions. Also, the narrative structure, such as whether it's linear or non - linear, is an important aspect of the outline. For instance, in 'Pride and Prejudice', the linear structure helps to clearly show the development of Elizabeth and Mr. Darcy's relationship. The setting of the English countryside in the early 19th century also adds to the charm and context of the story. And the themes of class, love, and pride play a significant role in driving the plot forward.