Paris in the last half of the 19th Century was a city on the move. It was a modern metropolis expanding into the future, with electric lights and steel towers. And yet its art was just as staid as it had been for the past 300 years. None of energy and innovation was translated onto the backwards-looking canvas. But some passionate young artists were about to rise up in revolt, to express an edgy new personal vision that would forever change art and the way we see the modern world.