darkness. poor visibility in the water because of the suspended sediment in the water. constriction constrictions. andtor tur ru and torture russ nature of the passages. it's not like a simple tunnel in a minor something like that, it changes shape almost continuously. >> i want to get a sense from you, because we're looking at video as you're explaining all of this, we're looking at exactly what you're talking about. we see what it's like for these crews to be in that cave. we see the wet and rugged terrain, we see the water that they'll have to dive into. no visibility in that water. look, two questions for you. this is a danger to the rescuers, right? it's certainly putting their lives on the line do this and certainly a danger for these young children, some of whom