China's Great Firewall fails

This week journalist and author James Griffiths explains how the Great Firewall of China works - and why it failed to stop the recent wave of protests there. Reporter Alasdair Keane meets the robots that could provide a helping hand to the most vulnerable. And game developer Colin Macdonald reflects on the unlikely origins of Grand Theft Auto, as the game franchise turns 25.(Photo: protestors on the streets of China. Credit: Getty images)