Over half of the world's population are living in cities. Beijing, as a national capital and megacity with over 21 million permanent residents, faces some unique challenges in its governance. In 2019, the city launched a reform designed to improve its response to public complaints. Its 64 existing hotlines were merged into a single 24/7 public service, the 12345 Hotline. The CGTN documentary Hotline Beijing brings you twelve stories illustrating how the reform, known as "Swift Response to Public Complaints", is supporting Beijing's efforts to build a better future for all.