Covid is back in the news - there is a new mutation of Omicron which is potentially more infectious than the last.

Some are sounding the alarm. We talk about whether you should be worried (spoiler -probably not). But while it's in the news we thought we'd examine a question long lurking at the sidelines of the Covid news story - where did it come from?

Is the lab leak theory increasingly credible? Plenty in Washington, including big elements of the Biden administration think so. And if it is - why are we not talking about it? What might be the biggest story of our time?

Lewis talks to a leading expert who sits on SAGE and a journalist who has done the running on the story from the very beginning.

Editor: Tom Hughes

Producers: Rory Symon and Alex Barnett

Social Media Editor: Georgia Foxwell

Video Producer: Will Gibson-Smith