January 23rd 2020. China takes an historic step – to quarantine an entire city. 9 million people were living in the central city of Wuhan – and locking the whole city down was a daring, though extreme measure, to try to stop a virus threatening not just China. But the world. With unrivalled access to Wuhan city under lockdown, and to the doctors, scientists, volunteers and public officials on the front line in this battle to defeat a new public enemy, this documentary charts the growing concern in China in the run up to lockdown, as scientists race to understand and control the virus. In honest interviews on location we discover the story inside the city after lockdown: the tension and stress, the courage and the commitment of the people of Wuhan. And find out how lessons learnt here could help the rest of the world in the battle to come.