Alan Yentob visits Egypt's National Museum, possibly the most precious museum in the world, with its dust-covered collection of thousands upon thousands of priceless ancient antiquities.The museum was caught up in the revolution on Cairo's Tahrir Square, standing right at the centre of the action. Its precious cargo was looted, and young revolutionaries formed a cordon around it to protect it.The museum is the heart of Egypt, containing the key not just to the country's past but to its future, offering inspiration and hope. Alan discovers that the pharaohs were not the slave-drivers of Hollywood legend, and that 4,000 years ago there was another revolution, foreshadowing today's, and even a goddess of social justice.With Omar Sharif and novelist Ahdaf Soueif.