How is the novel Mrs. Dalloway different from the conventional plot-driven novel?

In the most basic sense, a traditional plot hinges on action. A character or group of characters desire something; they act in such a way as to procure it; other characters will try and foil their plan. Thus, a traditional plot will involve a problem that needs to be solved - that is, actively and aggressively solved by a group of empowered characters.

The plot of Mrs. Dalloway, in contrast, revolves around internal thought and feeling, not action. Clarissa does very little in the novel: she plans her party, attends it, and appears before her childhood friends in a striking, if tragic, moment. Rather, emphasis is placed on Clarissa's memories, emotions, and silent monologues; similarly, other characters, like Septimus Smith and Miss Killman, are defined not by what they say and do, but what they feel and hold within themselves.

Mrs. Dalloway is revolutionary in the way it recasts not only the structure and flow of a novel, but also its proper themes. Whereas before, only grandiose feats and incredible activities were seen as proper fodder for a narrative (think The Odyssey), Mrs. Dalloway takes the quiet, seemingly bland mind of an English woman and spins it out in all of its hurt, complexity, and possibility. Thus, the small and hidden world of a woman becomes as important, and as worthy of writing, as a great battle, and clean, action-oriented plot structures are replaced by hazy meanderings reminiscent of thought.