Back pain is one of the world's greatest public health challenges. It is the leading reason we visit the doctor, the leading reason we take time off work, the biggest cause of disability worldwide. Around one in 10 people will develop chronic, life-ruining back pain. And rates are growing. A multi-billion dollar industry exists that claims it can fix back pain - by shrinking discs, melting nerves, cutting spines up and putting them back together. Yet leading experts say more often than not, all this expensive medicine is making things worse. Liam Mannix is one of the many who live with back pain, and he takes his own experience as a starting point for this compelling and urgent work of investigative journalism. In the last 20 years, a new theory has emerged, born from cutting-edge neuroscience. It claims back pain often has little to do with the back or the discs or the spine. Instead, back pain is all about the brain. This new science offers new solutions - including, remarkably, evidence that just by teaching people the new theory of pain we can reduce it.