Wuhan, China's economic heartland - and the epicentre of a global pandemic. Three years ago we set out to follow the fortunes of two companies as they fought to establish themselves in the city's Optics Valley, a dedicated zone for new technology enterprises. This is the story of some of the people who live and work in this city. And the story of Wuhan before and after the arrival of the coronavirus that would change all of our lives. Robotics CEO Xu Jishui struggles with setbacks, and software entrepreneur Huang Tiesen's relationships comes under pressure as he searches for funding to keep the business afloat.