John Coates's 'The Hour Between Dog and Wolf' explains how risk-taking and stress transform human biology, with profound implications for financial markets and human behavior under pressure. Coates, a former Wall Street trader who became a neuroscientist at Cambridge, draws on his own research and experience to show how hormones like testosterone and cortisol shape decision-making in ways traders and their managers rarely understand. During winning streaks, testosterone surges create feelings of invincibility that lead to excessive risk-taking; during losing streaks, cortisol-driven stress produces paralysis and irrational caution. The title refers to the twilight hour when the brain confuses familiar and threatening shapes, a metaphor for the perceptual distortions that hormones produce. Coates argues that understanding these biological mechanisms can improve financial regulation and individual decision-making, though he is realistic about the difficulty of overriding evolved responses. The book combines accessible neuroscience with vivid descriptions of trading floor culture, showing how abstract financial instruments are bought and sold by bodies subject to ancient biological imperatives. Readers interested in behavioral economics, neuroscience, or how stress affects performance will find original insights from someone who has lived and studied these phenomena.