Paris - Alexei Navalny’s organisation has worked ceaselessly to expose corruption in Russia with skillful use of social media and, just after his arrest, scored millions of views with a documentary about a vast and sumptuous residence on the Black Sea which, according to the organisation, was at President Vladimir Putin's disposal.

The documentary prompted tens of thousands to hit the streets, from Moscow to Yakutsk in Siberia where temperatures hit -50C. Why did people in more than 110 cities answer Navalny’s call to protest?

Episode 4: The Palace