This painting sat unfinished in Picasso’s studio for almost nine years, unsettling even his closest friends. We covered the influence of African masks, his ongoing dialogue with Braque, and the violent break from classical perspective towards Cubism (a completely new way of showing three dimensions on a 2D surface). Often described as ‘the birth of Cubism’, this work still feels abrasive, unstable, and a wee bit risky over 100 years later - little wonder it’s a central fracture point in modern art. Apparently it’s insured for a billion US dollars (gulp!) You can see it for yourself at MOMA in New York.