There were two reasons I wanted to watch this documentary. The first is because the making of the film itself, Fitzcarraldo, has a reputation for being infamously out of control and beset with problems, talked about in the same tones as Apocalypse Now, Roar, Jaws, Richard Franklin's The Island of Dr Moreau or The Shining.

But the less prominent one is because Werner Herzog is a fascinating figure, as soulful as he is intelligent and as stiffly formal as he is artistic. Being a much younger man back when he made this film (while the rest of us were watching ET: The Extra-Terrestrial and First Blood), I wanted to see what he had to say about the confluence of philosophy, filmmaking and failure deep in the Amazon jungle.

Herzog's journey here mirrored Fitzcarraldo's himself, and the delays, sticky heat and frustration must have rendered him hardly able to tell the difference between his movie and his life.

He's not shy about talking to his director, Les Blank (although it's been admitted a lot of Herzog's speeches and soliloquies were performed, not really given off the cuff), and though his face barely registers emotion at the best of times, you can see his mental state unravelling behind his eyes.

If it wasn't financing falling through multiple times, it was the threat of intertribal warfare among the local indigenous groups the production recruited to play parts or work behind the scenes. Like the natives who agree to help Fitzcarraldo pull his ship over the hill, Herzog and his producers never knew whether his crew would up stakes and disappear overnight for some unknown reason.

Funnily enough, Blank had as much trouble making his film about the filming as Herzog did. Whether it was the appalling conditions, being so cut off from civilisation for so long or the endless waiting, Blank had a diary from the time where he admitted towards the end that he was so over it all he didn't care if either he or Herzog finished at all.

Notably absent from the entire film however is how monstrous star Klaus Kinski was. He talks direct to camera in just a single scene where his belligerent nature is plain to see by the contempt he uses to describe their surroundings.

But the film doesn't even touch on the famous stories about how hated he was on set and how his prima donna antics held everything up as much as the financing and filming problems.