What an underrated movie - I wonder what Welles thought of the use of subjective camera. The effect is quite creepy, and it gives you some understanding of what an interesting movie "Heart of Darkness" could have been.
I can't seem to find much about the movie on the internet, apart from a few lazy reviews that just repeat the plot verbatim.
It takes a whole hour to get to see Bogart and have the movie presented conventionally; we only see things from Bogart's POV, and when we don't he is in darkness, or covered in bandages. How did the studio let director Delmer Daves get away with using a big star and not including him for more than half the running time of his picture?

