This third and final episode focuses on the world of art, dahling. Matthew Cain explores scientific research that looks at how the human brain processes pieces of art. An experiment at London's Tate Britain monitors the breathing, sweating and heartbeat of members of the public to find out how they respond to certain works (he suggests there's unconscious anthropological factors in popular art, fnar, fnar), and Professor Semir Zeki reveals what he believes to be a 'formula for beauty'.