If the conscious mind – the part you consider you – is just the tip of the iceberg in the brain, what is all the rest doing? Why can your foot jump halfway to the brake pedal before you become aware of danger ahead? What do Odysseus and the global financial crisis have in common? Why are people whose names begin with J more likely to marry other people whose names begin with J? And why is it so difficult to keep a secret? Our behaviour, thoughts and experiences are inseparably linked to a vast chemical-electrical network called the nervous system. The machinery is utterly alien to us, and yet, somehow, it is us. Neuroscientist David Eagleman plumbs the depths of the subconscious to illuminate this hidden world in his fascinating and engaging exploration of the human brain.