Broken Bayou is an example of the psychological thriller—a sub-genre that combines elements from both thrillers and works of psychological realism. Psychological thrillers are often character-driven as well as suspense-driven, feature protagonists who experience psychological distress, and explore the way that those mental and emotional states impact thoughts, perceptions, and decision-making processes. Fear, anxiety, and tension are often key textual undercurrents, and they drive narrative drama. Psychological thrillers often explore dark themes related to death and dying, existential crises, perception and reality, and the mind as a site of both analytical acumen and psychological unraveling. Characters in psychological thrillers are often engaged in serious inner struggles and are forced to confront difficult, even dangerous circumstances.

Psychological thrillers typically feature plot twists such as Willa’s abrupt realization that Travis, not his brother Doyle, is the area’s serial killer or her surprise revelation that her sister Mabry, whom she has been phoning and texting for the entirety of the novel, is actually deceased and died by suicide. Psychological thrillers also often employ unreliable narrators, characters whose version of events is not necessarily trustworthy. While Willa is not intentionally deceptive, she hides the truth about Mabry’s death from the reader because she has been unwilling to admit it to herself.