In Bournville, a placid suburb of Birmingham, sits a famous chocolate factory. For 11-year-old Mary and her family in 1945, it's the centre of the world. The reason their streets smell faintly of chocolate, the place where most of their friends and neighbours have worked for decades. Mary will go on to live through the Coronation and the World Cup final, royal weddings and royal funerals, Brexit and Covid-19. She'll have children and grandchildren and great-grandchildren. Parts of the chocolate factory will be transformed into a theme park, as modern life and the city crowd in on their peaceful enclave. As we travel through 75 years of social change, from James Bond to Princess Diana, and from wartime nostalgia to the Internet, one pressing question starts to emerge: will these changing times bring Mary's family - and their country - closer together, or leave them more adrift and divided than ever before?