coolest experiences you could ever have is diving but i holy madagascar isamazing.rickwitman ryan dart philip leiman are ex-ploeshers and about to go into this cave. >> we just passed the entrance and i'm going to proceed further into the cave. >> i'm with no giant ocean full of things know. >> crawlers here and there. >> we found where they make roaches, the roach factory. >> oh, no holy cow! is like crawling! >> one of those things get in your wet suit forget it. >> they gear up and, boy, oh boy, is this stunning. >> they have to sort of puttheir tre s for about two hours, so they have to make sure that they have enough oxygen. >> you don't want to bump into features you't want to cause damage so that's another layer of this >> they are very respectful of where they are. >> are those guidelines? >> yeah that's their and out. >> often times if you're not paying attention, you can get lost and if you run out of oxygen -- >> you dead. >> you stop. >> the dark cavy bit or the dark cavy pit. >> when they finish off cave they go to a second one and show us absolutely st