John Sweeney makes trouble for crooks, cults and dictators. First for the Observer and then the BBC, he has covered wars and chaos in around 100 countries and has been undercover in Chechnya, North Korea and Zimbabwe. The author of 16 books, including the Sunday Times bestseller Killer in the Kremlin, he has challenged both Donald Trump and Vladimir Putin face-to-face. His podcasts include Hunting Ghislaine, Taking On Putin and Lucy Letby: Was There Ever A Crime?