After years of rumours that the virus that causes COVID-19 escaped from a laboratory in China, the virologist at the centre of the claims has presented data on dozens of new coronaviruses collected from bats in southern China. At a conference in Japan this week, Shi Zhengli, a specialist on bat coronaviruses, reported that none of the viruses stored in her freezers are the most recent ancestors of the virus SARS-CoV-2.