Anna Fox is a fictional character from the novel "The Woman in the Window" by A.J. Finn. She is a former child psychologist who becomes agoraphobic, meaning she is unable to leave her home due to intense anxiety. Anna spends her days observing her neighbors through her window, which leads her to witness a shocking event. As the story unfolds, Anna's mental state deteriorates, and her reliability as a narrator is called into question. The novel explores themes of isolation, trauma, and the impact of mental illness, making Anna a complex and intriguing character in contemporary literature.