Who is Alexei Navalny?

A few months ago Russian opposition leader Alexei Navalny was lying in hospital in Berlin, recovering from being poisoned with the nerve agent Novichok. This week he was imprisoned after returning to Russia to continue his campaign against Vladimir Putin, despite the clear risks. But who is Alexei Navalny? And does his campaign have any chance of success? We talk to our correspondent Dan McLaughlin. Plus, the story of the Chinese writer first praised but then shunned for sharing her insider account of the Wuhan lockdown.