batters its way deeper into the cage, forcing the people to the bottom. >> i was on my couch physically watching like that. >> it takes a more frightening turn when the great white knocks out one of the diver's air regulators. >> this is your living nightmare unfolding right in front of your eyes. >> with no room left in the cage and oxygen running out, the diver takes matters into his own hands. >> he pushes it back, kind of able to when the shark turns to sneak his way out of the cage and back to the surface. >> the guy saw a gap and took it. and made it safely and the other guy followed suit and they both survived. >> and there's a twist to this shark tale. >> many people after this happening would never dive again in their life. but this guy was so passionate about it and decided to kind of turn it into a positive and become an instructor. coming up, you thought your job was tough? get set for occupational hazards from the terrifying -- >> i'm thinking this could end badly.