What goes on inside the mind of a mathematician? Where does inspiration come from? With a storyteller's gift, mathematics genius Cedric Villani takes us on a mesmerising journey through the discovery of a new theorem. Along the way he encounters obstacles and setbacks, losses of faith and even brushes with madness. His story is one of courage and partnership, doubt and anxiety, elation and despair. Blending science with history, biography with myth, Villani conjures up an inimitable cast of characters including the omnipresent Einstein, mad genius Kurt Godel, and Villani's personal hero, John Nash. We discover how it feels to be obsessed by a theorem during your child's cello practise and throughout your dreams, why appreciating maths is a bit like watching an episode of Columbo, and how sometimes inspiration only comes from locking yourself away in a dark room to think. Vividly described and compellingly told, Birth of a Theorem combines passion and imagination to take us on a fantastical adventure through the beautiful, mysterious world of mathematics.