Journalist Robin Aitken comes from a conservative political viewpoint to a man who has inspired mass movements on the left: Karl Marx. Robin who was a BBC reporter for 25 years thinks Marx was always in the background discourse of politics, an influence he partly feared and didn't fully understand. He takes a walk through central London in the footsteps of the great revolutionary. And in conversation with the likes of Paul Mason, Judith Orr, Marc Stears and Peter Hitchens he tries to find out what political and economic influence Marx retains today. Producer: Nina Robinson.