Every week seems to throw up a new discovery, shaking the foundations of what we know. But are there questions we will never be able to answer - mysteries that lie beyond the predictive powers of science? Marcus du Sautoy invites us to consider the problems in cosmology, quantum physics, mathematics, and neuroscience that continue to bedevil scientists and creative thinkers who are at the forefront of their fields. He challenges us to consider big questions - about the nature of consciousness, what came before the big bang, and what lies beyond our horizons - while taking us on a virtuoso tour of the great breakthroughs of the past. He celebrates the men and women who dared to tackle the seemingly impossible and had the imagination to come up with new ways of seeing the world. The mathematician holds the University of Oxford's prestigious Simonyi Chair for the Public Understanding of Science.