Locked away remote from the rest of the body in its own custom-built casing of skull bone, with no intrinsic moving parts, the human brain remains a tantalising mystery. But now, more than ever before, we have the expertise to tackle this mystery - the last 20 years have seen astounding progress in brain research. Susan Greenfield begins by exploring the roles of different regions of the brain. She then switches to the opposite direction and examines how certain functions, such as movement and vision, are accommodated in the brain. She describes how a brain is made from a single fertilized egg, and the fate of the brain is traced through life as we see how it constantly changes as a result of experience to provide the essence of a unique individual.