The opioid epidemic has devastated America. But what is the situation here? A new report from Public Health England raises serious concerns about Britain's own relationship with painkillers. Dr Michael Mosley embarks on an immersive journey to Britain’s opioid frontline and meets patients struggling with addiction and GPs fighting a constant battle to help those suffering from chronic pain. He also uncovers worrying evidence of people abusing over-the-counter opioids and discovers how easy it is to buy strong opioids online.