Documentary in which painter and critic Matthew Collings charts the rise of abstract art over the last 100 years, whilst trying to answer a set of basic questions that many people have about this often-baffling art form. How do we respond to abstract art when we see it? Is it supposed to be hard or easy? When abstract artists chuck paint about with abandon, what does it mean? Does abstract art stand for something or is it supposed to be understood as just itself? These might be thought of as unanswerable questions, but by looking at key historical figures and exploring the private world of abstract artists today, Collings shows that there are, in fact, answers. Living artists in the programme create art in front of the camera using techniques that seem outrageously free, but through his friendly-yet-probing interview style Collings immediately establishes that the work always has a firm rationale. When Collings visits 92-year-old Bert Irvin in his studio in Stepney, east London he finds that the colourful works continue experiments in perceptual ideas about colour and space first established by abstract art pioneers such as Paul Klee and Wassily Kandinsky in the 1910s. Other historic artists featured in the programme include the notorious Jackson Pollock, the maker of drip paintings, and Mark Rothko, whose abstractions often consist of nothing but large expanses of red. Collings explains the inner structure of such works. It turns out there are hidden rules to abstraction that viewers of this intriguing, groundbreaking programme may never have expected.