Seductive, fearless, and outrageous, Marina Abramovic has been redefining what art is for nearly 40 years. In this documentary, Marina prepares for what may be the most important moment of her life - a major new retrospective of her work, taking place at the Museum of Modern Art. For Marina, it is far more - it is the chance to finally silence the question she has been hearing over and over again for four decades: 'But why is this art?'.