Transcript for Mission is a 'go': Rescuers jump into action to save boys from Thai cave: Part 2

need great W. Reporteouds gather at Doi Nang non mountain, the rescue txiously awaits approval for its daring pl get that trapped socte of those N tunnels. Had you waited morday, what do you thinkould have happened? If I wait one more day, I ink that it would have been for us bee the is coming.orter: Agonizing H pass. Then finally M the thairime nister himself, the rescue miss ." It's about 6:00 P.M. Nigh ich, thankfuwas when we finisd up with L of our aserations. We were Y to go at tt T. What was your reaction when od that th is happening? Relief that we coget on with it but also the nervousness that we would act do it. Translator: Today is d-day. We are ready. These are the first boys to be rescuore and me arriving. Reporter: Now, the waiting ves way to sudden, fur action. Een curtain to block ve's entrance, as a parade of divers is seen rmous cache of extra air deplo in T chambers throughout the cave. Divers, each boy at a time -- I that's correct. That's a tremendous amount of responlity. Yeah, very muo. But when the br reh that faraway cavern where the team is trapped, they find thmss are G the rrifying oea're facing. There was no sign of distressno hint ofroblem. Extremely ident brav brave young men. Eporter: Ifact, the ai cte the cave wite wild boars says theyide on N what order the going to go out in. Translator: It was a decision made by all the bs becau theirsical and mental conditions same. E boys whoived farthfrom E T first because they cycle home totheir Parente news. Reportef course, those parents had never left the cave nce the oral began. But choosiho is firsin line is actually no small desion. That boy will be a Sor Guinea pig in a first of its kind rescue.ls to mall to shephehe boy outafely.u pull thehort straw of takthd out? I volunteered.o take the first ou I'mothang around in the back. So I just vun child walks down a steep slope into the W. Ime for an absolutely critical step, agreed to in advance by the Thai government. The boy is injected with a commonly-use ketanelian diver Dr. Richarharris an anesthesiologist. And mallinreveals th the shot is not just tlax the can't have him twitching aroundwhen they stmoving the moving around. There's potential for them to ki themselves. There was potential for them to kill us. It wasuch betteror me to Seda Heep him under. So itas basically an ultimatum from the British thisperation, unhose kids are sated. Tely made at a red line. Like, "Yeah, if gonna try is iit's gonna be essful, thki be se Reporter:er receive that injecon, the first boy is out cond ready F the next step oe rescue. Just like in thoraining sessions, L face mask is strappedhtly on. Single leak could be potentially fatal. The child is now fully prepped and readto go, yethe veteran rescue diver is still assa with doubt. I W confident of being ableto take one ids and them out. I was T confident ING them out alive. And why W that? Bau't know at first, how they were goio acater, whetr that we'diven thewould be sufficient toctions. Reporter: But Mallinson is not one fo he enters thcold, murkwater with T first dive stage. Remember, it's meters lo, . 3 1/2 football fields. What follows nex a sort of cheogrd underwat ballet. With one hand, mlinson has to hold onto the E that stretches to these, while the other hand is holding tight to a strap on the S obstacles in the way. Coursehat you do completely. Ich you arblind. The obstacles on the way in. Rorr: Mallinson says his biggest concern,in E mask doesnome ose. Was thereec if their faces air tank malfunc? There was no otoption. We wouust have tsw to getoulooded section to the next air chamber. And hope that they T die along the way? I mean that's when we were using almost pure oxygen, 80% oxygecause we had been told that, you knowsurvive fo several minutes notbreathing. Reporter: After about 20 painsta, agonizin minute Mallinson sucfully mpletes thrst dive sge. Waiting for him are two support divers who help him get the unconscious out of the ter. Theyive him a medicheck, but with five more dive stages to go. They are far from woods. Repr: Coming , of crisi Mallinson is in complete up to hisneck in war, unthinkable happens, houng charge starts waking up. You realize you've got redminister the sedation take veteran dir himselout of Thi situation?isolated aes in your E? Ever. The responsibility was huge.

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