tonight on "nightline" -- the incredible power. the majestic fury. unleashed. we venture into the most explosive place on the planet. >> when you're this close, you not only hear that boom, but you feel it. >> with a team of thrill seekers, and one unlikely adventurer. >> what can go wrong? >> willing to go to hell and back. >> five meters. two meters. oh, my god. >> in pursuit of the ultimate shot. the stakes are high. >> you could die. >> as we face off with one angry volcano. a special edition of "nightline," inside the ring of fire, starts in just seconds.

this is a special edition of "nightline," inside the ring of fire. >> good evening and thanks for joining us. japan's mt. ontake is still erupting tonight, after a blast covered hikers in suffocating ash. an estimated 36 people died in the tragedy. so, why would anyone visit a volcano? on purpose? tonight, we're taking you on a journey few have braved before, to a remote island that's home

to one of the most violent volcanos on the planet. abc's gloria riviera is heading into a ring of fire with some intrepid experts to experience the death-defying drama of earth's 3,000-degree oven. >> reporter: the sheer force of it is like nothing else on the planet. when you're this close, you not only hear that boom, but you feel it. what you see is stop in your tracks stunning. we're inside the ring oaf fire. the most explosive terrain on earth. bearing witness to one of nature's most violent and unpredictable forces. and at the center of it all, 11-year-old molly ambrose. the world's youngest volcano

hunter. >> came a long way and the only way to here is by boat. >> reporter: she's traveled end gleez with her father, rad. >> can you hold onto my bag? >> reporter: who makes a living filming rare images of nature's most explosive threat. >> i can smell something burning. everything about a volcano is different. they have different personalities. >> reporter: and right now, they're venturing to one of the angriest. to capture the ultimate shot of this violent volcano, located on an uninhabited island. what are the changers on a volcano? >> lots of things could go wrong. when the lava shoots out of the crater, it could hit you and you can get burned or a rock, you can get hit in the head. >> the longer you sit around a dangerous place, something bad will happen. >> reporter: leading this indonesian odyssey, jeff

mackley. a legend in the business. >> at the moment, i'm about as close as you can get to the volcano. >> reporter: and a lifelong adrenaline junky. >> it's like a drug. when you find something you like, you do it again and again even though it may cause you harm. i think that's how you describe that. that's the goal, down there. five meters. >> reporter: together, these new zealand natives have been to hell and back. >> oh, my god. oh, jesus. >> reporter: cashing in big with breathtaking footage like this. just feet from a chaotic caldron of bubbling lava. >> what did it look like? >> looks like the surface of the sun. it looks like all of my wildest dreams. >> reporter: it's pictures like these that have made them famous. but new adventures beckon. the more remote and difficult the journey, the greater the prize. and we want in. so, we asked them to be our guides. but can they really pull it off

with a child in tow? every time you go out there and you get on a volcano, what are you hoping for? >> i'm hoping to come back alive. >> reporter: so am i, because this journey will be treacherous. indonesia is home to a record 147 active volcanos. and on our way, we pass through this hellscape. a volcanic sulfur mine engulfed with toxic gas. a large enough eruption could unleash a giant active lake on everyone below. water so toxic it dissolves metal. it is risky, even for the adults who work here. and certainly not ideal for an 11-year-old. >> what do you think of this place? >> it's cool. really cool. >> reporter: this is an inherently dangerous and unpredictable place. does molly have any place being there? >> i think so. she's getting world experience that she's not going to get anywhere else. there's only so much you can

learn from looking at a tv screen or experiencing it on a computer. >> reporter: brad, a divorced dad, is almost always on the road. and if molly didn't come along, he says he'd barely see her at all. >> because i actually live four, five hours away from her, i want the time that we have together to be special. >> reporter: this volcanic mine is a first for molly, but jeff's been here before. >> it's been ten years since i was last here and things have changed a lot. now the tourists outnumber the miners, probably 100 to 1. >> reporter: volcano tourism is the latest trend in adventure travel. and that's a problem for jeff, because no client is willing to pay to be dollar for pictures anyone can get. to stay at the top of his game, he has to up the ante. how far are you willing to go to get those shots? >> oh, to the ends of the earth. >> reporter: and that's exactly where we're headed. >> it's one of the most active volcanos on earth at the moment. but a place most people have never heard of.

>> reporter: let alone seen. we take two planes -- >> hey! >> reporter: a long drive. and hook up with a local guide who helps us hitch a ride on a tuna fishing boat for the final leg. the only way to get out to this volcano is to take one of these boats, six hours at least, we're told it's going to be pretty bumpy. >> disappear for a couple of days and go fishing. and hopefully they come back. >> reporter: this is the flores sea and we are surrounded by volcanos, stretching 25,000 miles around the pacific. this ring of fire is home to 90% of the world's earthquakes and by far most volcanic eruptions. you have tsunamis, earthquakes, volcanos. is the ring of fire the most volatile place on earth?

>> i'd call it necessary. if you didn't have the that stuff going on, the earth would be tearing itself apart. when you go to these places, if you've got something, you don't have it. if you need a hospital, there isn't one. if something goes wrong, you're screwed. >> reporter: our local guide says fewer than 50 westerners have ever braved the journey. certainly none as young as molly. >> maybe she should move with daddy. >> reporter: the trip is brutal. six grueling hours on a dodgy boat, beating into oblivion. only molly keeps smiling. the rest of us, queasy. >> it's erupting right now. >> reporter: oh, yeah, look. oh, my god. that's huge. it's almost like on cue. just as we started to get close, it erupted. almost as a welcome, or maybe a warning. >> reporter: one by one, we load

up. >> high five. we made it. >> reporter: even this strange pae passenger. our guides insist we bring him along as a sacrifice. an idea molly hates. we're now on sacred ground. low cams have always steered clear for fear of upsetting the mountain. that's it. we're alone. we're alone out here. when night falls, we goat work. and with only 48 hours on this island, every second counts. what do you have to do to get the shot? >> well, you pretty much got to stay awake with a camera aimed at the action for as long as it takes to get the action. you don't know when that's going to come. or if you're going to run out of batteries before you get the action. >> largest eruption we've had so far happened -- >> reporter: yeah. >> so, now i'm going to go and see how big it really was. >> reporter: the guys are able to film a few decent eruption,

but not the shot they're after. we have no way to predict just how violent each eruption will be. so, what is the safety plan there? >> there isn't one. >> reporter: there isn't one. >> you're on an active volcano. the safest thing to do would be not to be there at all. >> reporter: the terrain here is unforgiving. the elements, extreme. and when brad and jeff are distracted, molly falls on jagged rocks, injuring her elbow. >> molly was behind us while we were talking and she slipped on a rock. and it only happens, what, 20 centimeters behind me. >> reporter: yeah. >> she needed dad. and there was an oh [ bleep ] moment. oh, gol oh, god. this is the first night. >> reporter: the night only gets worse when we attempt to sleep in our makeshift camp. we've had a major rainstorm tonight. we've had a few really, really big explosions.

we're having huge problems right now because this tent is basically collapsing. >> at the same time, we realized that the sea is starting to invade our camp to the point that the waves are cashing so close, they are coming inland and hurting us. it was kind of like hell. >> reporter: we're trapped between an erupting volcano and swelling seas. at this rate, i'm not even sure how we'll get off this island. coming up, we face the full r h rath. into one you'll never forget. earn points for every flight and every hotel. expedia plus rewards. feel like a knot.

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and we're back tonight, inside an explosive volcano. even the locals keep their distance.

we're going right in. with rain pouring down from above and lava bubbling up from below, our quest is on to capture the staggering and deadly beauty few others will ever see. here again, abc's gloria riviera. >> reporter: i'm in the heart of the pacific ring of fire with a trio of danger-loving volcano hunters. look at that. including 11-year-old molly ambrose. these intrepid photographers in pursuit of the ultimate shot that have led me to a remote, uninhabited indonesian island. and one very angry volcano. we only have two nights here and we barely survived the first. battling crashing waves and torrential rain. come morning, the tide is threatening to overtake camp. instead of filming, they're scrambling to build a barrier. >> it's still quite sore. >> reporter: and molly, she's still a little shaken up.

>> sometimes i get a bit scared, but dad says, the good thing is, when you're scared, it's because you're thinking about all the dangers. >> reporter: right about now, her dad's mostly scared because thousands of dollars are on the line and he still hasn't captured the shot. they are racing against time. >> we pretty much lost half the day just waiting for the weather to start clear egg. ideally, there's so many other positions we want to be in. >> reporter: getting any closer by boat is out of the question. >> the money shot's doing something ridiculous on camera that doesn't get you killed. >> reporter: now the locals are saying, they think the mountain is pissed off with us, we didn't make any offering. >> well, kill a chicken. >> reporter: kill a chicken? remember this poor soul from the tuna boat? well, desperate times -- >> so this chicken actually we would like to sacrifice. >> reporter: the guides hope now our luck will change. call it coincidence, but after a few hours, the weather improves.

we set out on an expedition to get even closer to the eruption. i mean, i can't believe how close we are. that is insane. the volcano, it seem, was expecting us. >> very beautiful. but it can kill you. >> reporter: it can kill you. >> yeah. >> reporter: but the real show happens after dark. so, we made it close. we didn't get the explosion we wanted. we have to move positions. now we're hiking at night, much harder, to try to get a better angle. holy crap! oh, my god. that is amazing. you can see all those rocks, those lava boulders coming down that chute. sounds like thunder, fireworks, an airplane taking off, all at once.

that is a fireworks display that only mother nature can do. >> the ones that you feel before you hear, those are the ones that you think, god, i hope, you know that they're happy with us. >> reporter: as the night wears on, brad's pursuit of the shot borders on obsession. >> i think i've got everything i need, but you always want one more. done. good time. i've done it now. >> reporter: but was it worth the risk? especially for molly? you're talking about a place that is unpredictable. there are no guarantees. if things go wrong, they would go very wrong and you're taking your daughter to those places. >> i think the journey is almost more of a risk. crossing a road, jumping in the car -- >> reporter: i don't know people will buy that. >> to me, she's the most valuable thing in the world. i wouldn't want to put her in a

place where i'm not comfortable being. she also balances me out. by having her with me, i don't push it as much as what i may have. >> reporter: brad and jeff court danger, but for half a billion people living in the shadow of she's slum perring giants, volcanos are a constant threat. >> it's the ultimate life-giver and life-taker. >> reporter: right now, two major eruptions are threatening catastrophes. one in iceland. the other in the philippines, where 50,000 people are being forced to flee their homes. volcano hunters are more than just thrill seekers. guys like jeff and brad actually spend more time on volume kay knows than most scientists. and they're indelible images are clues that help us piece together the mystery of these natural wonders. potentially saving lives. after two hellish days on this island, i'm eager to leave. but not molly. >> stay the night and watch the eruption.

so, i wouldn't mind staying here another night. >> reporter: brad's thirst for adventure must be hereditary. what do you want to be when you grow up? >> i just really want to follow dad's footsteps. >> reporter: for this father and daughter team, a trip that took us all to our very limits, but brought them even closer together. >> the one constant we have is time and it keeps passing. sooner or later, she won't need me anymore. >> i will always need you and i will always love you. it's good to spend time with him. >> reporter: even if it means it has to be on a volcano. >> yeah. >> reporter: for "nightline," i'm gloria riviera in indonesia. >> our thanks to gloria and producer nick for that incredible report from the ring of fire. next, is there anywhere the venn or the of the go-pro hasn't gone with his famous gadget?

turns out, the answer is yes. and we're taking you with us. in with his famous gadget? turns out, the answer is yes. and we're taking you with us. v with his famous gadget? turns out, the answer is yes. and we're taking you with us. en with his famous gadget? turns out, the answer is yes. and we're taking you with us. t e with his famous gadget? turns out, the answer is yes. and we're taking you with us. o gone with his famous gadget? turns out, the answer is yes. and we're taking you with us.r & pandwe'r takg yo ocf

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and finally tonight, we're taking you to new heights with a man who was named one of forbes youngest billionaires today. thanks to a little invention he calls the go-pro. a cool $4.9 billion later, is there anywhere his celebrated camera hasn't been? here's abc's "world news tonight" anchor david muir. >> the corner of faift avenue

and west 33rd street here in new york. where they're waiting for us with their own cameras. the inventor of the go-pro. right there with a camera for me and a camera for him. and this is the first time he's tested out his cameras at the empire state building. nick woodman came up with the idea. just 26, he's a surfer. attaching that camera to his surfboard. but his intentivention has the american family in mind. taking america to the top of the empire state building. to the observation deck, walking through that door and just look. >> you got to be kidding me. >> look at this. lower manhattan. if you look closely, right through those metal barriers, you can see it. the freedom tower standing high above the rest. but our next stop was even higher. right up there, in the shadow of the spire. >> i got to hang out with you more often. you get to go to the cool spots. >> right up to the 102nd floor. we go up one last set of stairs. this is exclusive access. >> all right. >> we climb the stairs, more

than 1,250 feet up. the 103rd floor. and just look at the view tonight. >> beautiful. thanks for watching abc news. tune into "good morning america" tomorrow. and as always, we're online at abcnews.com. good night.