Filmed over three years with unprecedented access, this documentary captures the return from California of England's favourite living artist. As Hockney approaches the age of 70, he re-invents his painting from scratch, working through the seasons and in all weathers out in the Yorkshire countryside, ending up with the largest picture ever made outdoors. It is at once the story of an unusual homecoming and also an intimate portrait of what inspires Hockney as his time runs out.