Le Mystère Picasso (1956)
The 1956 film Le Mystère Picasso (The Mystery of Picasso) shows Picasso at work in real time, mostly on a glass canvass allowing the viewer to see first hand the work of the great artist. Most of the works that appear in this movie were destroyed following filming so that the works would exist solely in the movie itself. The movie won the Special Jury Prize at the 1956 Cannes Film Festival.
The Mystery of Picasso is available on Amazon.