The film portrays a fictional account of conquestadors exploring the Amazon, but takes nearly all of the plot from various historically recorded events. Filming itself, in the Bolivian jungle is the stuff of legends and many of the scenes are simply capturing the difficulty the actors had carrying their gear / travelling on the mighty Amazonian rivers. If you've been to the Amazon or are interested in the history, I can recommend this. If not, you may want to think twice. The key downsides is the inexplicable plot - we really don't get to understand any of the 'why's' in this film, and the interminable footage of the crew travelling down the river. The dubbing is terrible, the music superb. I'm surprised this film hasn't been remade as the story itself is fascinating, but as it stands, this is a flawed classic and even at 90 minutes seems overly long.