The caves are amazing but the narration is terrible. Repeating "it can kill them" and "one mistake is certain death" is total nonsense. Yes, there are risks but this is typical over dramatisation. The tone is so over exaggerated detracting from the sheer majesty of the caves. We get the point it's hot and humid down there. Being told twenty times is not necessary. It's gets a five for the amazing crystals but the terrible script prevents any higher rating. It tries to big up the risks time after time. Becomes irritating very quickly. It could be so much better if the scriptwriter were sacked and someone capable hired.

As most cable produced documentaries, it has too much drama. The subject is very interesting and beautiful but the artificial suspense and drama tone made me lower the rating and jump large parts of this while watching. It's time for the cable productions to change this, no one can bears excessive useless drama anymore.