When the Mona Lisa was stolen from the Louvre in 1911, thousands of people flocked to see where it had once been on display. Many of them had never seen the painting in the first place. What could have drawn these crowds to an empty space? And can this tell us something about why we look at art, why artists create it, and why it has to be so expensive? Taking the intriguing story of the Mona Lisa's two year disappearance as his starting point, Darian Leader explores the psychology of looking at visual art. What do paintings hide from us? Why should some artists feel compelled to lead lives that are more colourful than their works? And why did the police bungle their long investigation into the theft of Leonardo's masterpiece? Combining anecdote, observation and analysis, with examples taken from classical and contemporary art, Leader discusses such seminal figures as Leonardo, Picasso and Duchamp, as well as Bacon, Lowry and the Young British Artists. This is a book about why we look at art and what, indeed, we might be hoping to find.