Fear and loathing in La Liga

It's Messi vs. Ronaldo, it's the greatest team of our time vs. the greatest team of all time. It's more than a game. It's a war. It's Barcelona vs. Real Madrid. Only, it's not quite that simple. From the wounds left by the Civil War to the team's current global domination, Spanish football expert and historian Sid Lowe lifts the lid on football's biggest rivalry.