Is the country at breaking point? For many, high levels of immigration have caused real issues and arguably led directly to the Brexit vote. But is Britain really full? For Dispatches, Michael Buerk investigates the story behind the numbers and the impact of internal migration. New research reveals the true scale of massive movement within the UK and its impact on both overpopulated and underpopulated areas. Buerk travels to a northern English city that has almost halved in size over the years, meeting young people forming the exodus of migrants heading south for opportunity and better pay. Here he finds forgotten streets full of empty homes. The North-South divide is not just about wealth but also about numbers. Buerk asks whether we ignore the issue of internal migration at our peril and whether, with Brexit on the horizon, this issue will finally be discussed.