BOY: Hey you! DIVER: How many of you? NARRATOR: For
almost three weeks, 13 young lives hang
in the balance. JASON: We didn't want
them to die and we didn't
want to die ourselves. NARRATOR: Then,
against all the odds. REPORTER (over TV):
Mission impossible has
become mission incredible! NARRATOR: One of the
greatest rescues of all time. PASAKORN: It was
like a miracle NARRATOR: But questions remain. How did the boys get trapped? Why was it so hard
to rescue them? MARTYN: The prospect
of a diving rescue was hideous from the outset. NARRATOR: And how was it done? CHRIS: Nothing like this
has ever happened before. JASON: Everything
was experimental. NARRATOR: Now, with
unprecedented access, a team of cavers conducts
the first ever 3D scan of Tham Luang, to
uncover the answers. Reconstructing the
cave in perfect detail. ROO: We're going to be able
to actually show what that passage was really like. NARRATOR: Transforming
our understanding of the Thai Cave Rescue. VERN: If two of them came
out alive that would've been a good result. (theme music plays). NARRATOR: 13 young
survivors and a moment
few thought possible. BOY: Thank you so much. (speaking in native language). BOY: Thank you. NARRATOR: Leaving the hospital,
after an astonishing escape and a terrifying ordeal. 25 days earlier, a school
soccer team, the Wild Boars, enjoyed a day trip
to Tham Luang cave. This is the last picture
taken before they entered, as night fell they
were still inside. REPORTER (over TV): A dozen
member of a youth football team and their
coach are missing. REPORTER (over TV):
Thought to be trapped
in an underground cave. NARONGSAK: Every
minute is important. NARRATOR: It would take 18 days, 17 cave divers, 200 air cylinders,
a mile of rope, 10,000 volunteers from
over 20 countries, and one death, before they could bring the
Wild Boars out of the cave. PASAKORN: The whole world
had their eyes upon us to see what we would do. REPORTER (over TV): We begin
tonight in Thailand with the life and death drama that's
captivating the world. NARRATOR: The drama played
out deep beneath the Doi Nang Non Mountains
of Northern Thailand. Ten months later, a British
team of cave explorers sets out to conduct the first
ever digital 3D survey inside Tham Luang cave. They will journey deep inside. Hoping to discover
the truth behind the extraordinary events of 2018. Leading the expedition is
cave explorer Roo Walters. ROO: When the divers
entered these caves, they couldn't see a thing. They literally felt
their way through. So we're going to show what
that passage was really like. NARRATOR: Now that
it's the dry season, the team can penetrate
the darkness to deploy
the latest technology and scan the cave in
forensic detail. ROO: It'll start to reveal
just how clever and how inspirational this
whole exercise has been. NARRATOR: Even in
the dry season, working here will
be challenging. After two hours, the survey
team is in a squeeze. MAN: And then it
closes down again. NARRATOR: Trying to reach
the place where the boys were eventually found,
to begin their scan. MAN: How you doing there? Yeah? NARRATOR: They reach an
area called Chamber 9. ROO: It changes
direction here Joe. JOE: Yeah.
Got a line up here. NARRATOR: This rope, put in
place by the rescue divers. To help guide them
through the silty water. JOE: Oh. Wow. ROO: Wow look at this!
It's the end of the line Joe. NARRATOR: It was here
the boys took refuge. JOE: That's quite
something isn't it? ROO: That really
is something... Gosh! NARRATOR: Left behind, foil
blankets and remnants of survival from 18
days underground. JOE: Wow. Not a lot
of space is there. ROO: It's not a lot of space. NARRATOR: And an insignia, left
by the four Thai Navy Seals who joined the boys on
this muddy ledge for 8 days. ROO: This is incredible,
absolutely incredible. JOE: It's something
else isn't it? ROO: It's emotional, it is. NARRATOR: They can now
start scanning the cave. Sending out 300,000
laser beams a second and recording every reflection
back from the cave walls. The team hopes its data
will explain exactly how the boys got trapped. Ten months earlier, the first
rescue team was on site. A mile inside the cave they
made an alarming discovery. The passage they knew the boys
had taken just hours earlier was now, full of muddy water. Where had it come from? And why had it
risen so quickly? To find out, the survey team
must scan the cave system from where the boys were trapped,
all the way to the entrance. The team works its way
through the tunnels, scanning every
crack and fissure. ROO: Alright Joe?
JOE: Yeah all good. NARRATOR: After half a mile
they reach a point they think is critical, called
Sam Yek Junction. ROO: I think this must
be Sam Yek Junction guys. JOE: Yeah. NARRATOR: The data
they collect at Sam Yek
junction will be vital. Feeding it into powerful
computer software, we can now recreate the first
section of the cave system, in perfect 3
dimensional detail. This is Chamber 9 where the
boys were finally trapped... And this, the half mile
long passage back... to Sam Yek junction. But a closer look at
Sam Yek reveals a clue. Another tunnel,
Monks series, joins the
main cave system here. In the rainy season when
these caves fill with water, Sam Yek becomes the
meeting point for two
underground rivers. Water finds its way through
the cracks and channels of the limestone mountains into
Tham Luang's cave system. VERN: This mountain is just
a big sponge and during the rainy season there's a huge
volume of water travels through Tham Luang Cave,
basically like a big river. NARRATOR: Back in 2018 when
the boys and their coach started exploring, there
was no sign of rain. They had no difficulty walking
through Sam Yek Junction. But outside, the weather
was changing fast. The heavy monsoon rains
had arrived weeks early. Almost an inch of
rain fell in an hour. Water seeped through
the limestone mountains, funneling down
into Tham Luang. And then at Sam Yek
junction, the other passage, Monks Series, brought yet
more water into the cave. At Sam Yek's narrowest
point the junction
filled in just an hour, flooding it to the roof. The boys were now sealed
inside the cave system
with no way out. ROO: Sam Yek is the crux of
this story and the 3D model clearly shows how that water
then flooded the cave and entrapped the boys. VERN: It was very isolated. There was actually
nowhere for them to go. NARRATOR: As rain
continued to fall... water levels rose further. Forcing the boys deeper
inside as they looked
for higher ground. So how did they survive? ♪ ♪ NARRATOR: Desperate local
officials called in the country's elite divers
to search for the boys. The Thai Navy Seals... But the still rising
water and strong currents
forced them back. OMAR (over TV): Relentless
rain is jeopardizing an already risky operation. REPORTER (over TV): They
believe that there has been flash flooding inside. OMAR (over TV): The
desperate race now is
to find another way in. NARRATOR: Above ground
armies of cavers scoured the mountains looking for a way
into the cave from above. The search was
gathering momentum. On day 9, a breakthrough. Electric pumps reduced
the water levels. Making it safe enough for
the Navy Seals to dive. They hunted for signs of
life, deep inside and laid a guideline to mark their
route back to safety. JOSH: We didn't really know
exactly where the boys were. I thought it was probably more
likely they were dead than alive at that point. NARRATOR: But
they weren't dead. So how did they survive? Revisiting the data
of the flooded cave
reveals the answer. This is Sam Yek. Where the water rose quickly,
trapping more water behind it. But here in Chamber 9, the
boys managed to find refuge. Discovering a solitary
shaft off the main passage. They scrambled up 14 feet
above the water line. It's a safe haven, in
a dark lofty hollow, that reaches 124 feet
above the rest of the cave. This was the only space in
the cave in which the boys could have survived. But a closer look at
the cave data shows an
intriguing anomaly, at the highest point of the
boy's refuge a small cavity, two and a half feet
wide and 9 feet long. ROO: It doesn't look like a
normal piece of cave it really sticks out and that's
because it isn't. NARRATOR: Revealed in the
data, for the first time, a tunnel the boys dug out. ROO: It's amazing. Little stone tools
are still there, scratches in the sides of
the walls are still there. What must have been going
through their minds as they dug with no idea of how far
underground they are. NARRATOR: Could the boys
have dug themselves out
from Chamber 9? How far underground were they? To find out, the team need
to do more than just survey inside the cave. They must also discover
exactly where Tham Luang lies, beneath the mountains. The investigation
takes to the air. ROO: We can connect the cave
3D model to the surface model and from that we'll actually
be able to work out exactly how far the boys
were underground. NARRATOR: Combining this aerial
data with the underground scan, we can pinpoint exactly
where the boys were in the mountain, one and half miles from
the cave entrance, and above them, lay 2,000
feet of solid rock. Accurately revealed
for the first time, the boys' complete isolation. Digging a tunnel was futile. ROO: What we've discovered, is
just how remote the boys were. It must have been
terrifying for them. NARRATOR: Dive teams
had searched the
flooded cave for days. Two British cave-divers
joined them, helping to lay more guideline. Then, a mile and
a half inside... REPORTER (over TV):
Dramatic scenes in Thailand. REPORTER (over TV): Against
all odds rescuers in Thailand have found 12 missing boys. REPORTER (over TV): Well
what an amazing day. REPORTER (over TV): For family
members pure elation after a heart-breaking waiting game. NARRATOR: The boys had
survived underground for 10 days with only the water
dripping from the cave walls to sustain them. Within hours the Thai
Navy Seals delivered food, medicine and foil blankets
to prevent hypothermia. But one thing was on
everyone's minds... VERN: Very quickly we
realized that our problem
was only just beginning. JOSH: Finding them
is one thing but what
are you gonna do next? NARRATOR: The Thai
Authorities were desperate
to find a simple solution. But it would take another 8
days of nerve-wracking and dangerous work to
get the boys out. MARTYN: Little did we know
how long and how complex that operation was going to become. NARRATOR: The Thai Authorities
identified three options... One: wait for the monsoon
rains to pass so the boys could walk out of a dry cave. But that would take months. Two: find another route
into the cave from above. But a week of mountain
searches discovered
only dead ends. That left option three, the
most extreme-sounding of all. REPORTER (over TV): Are
they gonna have to learn
how to scuba dive their way out of there I
mean that's really a tall order. REPORTER (over TV): Yeah
it's crazy isn't it. PASAKORN: We came to the
conclusion that the only way to bring the children out was
the same way they went in. MARTYN: The prospect
of a diving rescue was
hideous from the outset. NARRATOR: What is it about
diving in Tham Luang that makes it just so dangerous? NARRATOR: It takes three weeks
for the survey team to scan Tham Luang cave. All the way from Chamber
9 to the cave entrance. The boys were one and
a half miles inside. But they were safe, and divers
had managed to navigate the flooded tunnels to reach them. So why was it so
difficult to get them out? To understand, takes big data. The team pieces together
nearly 400 scans and builds a virtual cave system... ROO: So this is full res. JOE: The detail in
that roof is fantastic. NARRATOR: A new visualization
of this underground world. ROO: We will start to be able
to show everybody what this cave is really like. It is gonna be quite magical. NARRATOR: With the world's first
3D digital survey of Tham Luang we can reveal the second
section of the cave system, all the way from
Chamber 9 to the entrance. 8.7 billion data points, more than 7000 photographs, come together to build
the flooded cave as it
was in July 2018. Draining its water,
for the first time.... Exposes all of its
subterranean secrets. This is Chamber 9 to Sam Yek and now, the rest
of Tham Luang cave, a narrow tunnel, that
widens to the entrance. All together one
and a half miles, the boys' only route out. Adding the water level of
the time to the digital map reveals why Tham Luang's
passages can be so lethal. In some places,
underground canals formed. In others, the cave
flooded to its roof, fully submerging the passage, in five sections known as sumps. The longest sump lay
next to Chamber 9,
over 1,000 feet long, the length of seven
Olympic swimming pools, taken together there were
half a mile of sumps, standing between
the boys and safety. And the visibility
was almost zero. The only way to escape
Chamber 9 was a long perilous cave dive
with air tanks, a potentially deadly option, even for Thailand's diving
elite, the Navy Seals. JONGKLAI: The Thai Navy Seals
who assisted with the rescue had only trained in open seas. They'd never dived in
very narrow spaces. NARRATOR: They needed
specialist help. A local caver, Vern Unsworth,
had been part of the search and rescue
mission since day one. After seven years exploring
Tham Luang he well understood the challenge ahead. VERN: We needed expert people
out here, and, you know, at the end of the day it
was the right decision. NARRATOR: He gave the Thai
authorities a list of some of Britain's most
experienced cave divers. An elite team arrived,
including John Velanthon, Rick Stanton, Jason
Mallinson and Chris Jewell. They are among just a small
group of people in the world who had the unique skills
needed inside Tham Luang. CHRIS: When we realized this
was the best chance of the boys getting out alive, then we were determined
to give it our best shot. NARRATOR: A rescue
plan developed. From the entrance, the first
half mile of cave was dry. At the end of it, Chamber 3. This would be dive base. From here, four cave
divers would head deeper into the flooded cave. Three hours later they
would reach the soccer team. Four boys would be
equipped with scuba gear. Then each diver would
return with one boy at 30-minute intervals. If everything went to plan,
it would take a full day to extract four boys. On their way out, each
diver and boy would need replacement air tanks. So, they placed 50 of them
throughout the cave and seven support divers would wait
between sumps to haul equipment and provide
medical backup. It was a rescue
plan like no other. CHRIS: The situation in
Thailand was unprecedented. Nothing like this has, has
ever happened before. Not those kind of distances and
certainly that number of people. NARRATOR: There were nearly
100 divers on site. Emergency services, the
US Army and volunteers, also out in force. All prepared and
rehearsed for the first
underwater extraction. At 1:30 AM, tragedy. VAUSE (over TV): Breaking
news out of Thailand. Where a former Thai Navy
Seal has died during
rescue operations. NARRATOR: Saman Kunan, seen
here with the rescue team, was on an overnight mission
to place air cylinders inside the cave. It's believed his
own air ran out. REPORTER (over TV): This has
taken on a whole new level of seriousness, there's a sense
of mourning here today. REPORTER (over TV): It's
raised serious doubts about how they'll get the 12 boys
and their coach out alive. NARRATOR: How would the boys
escape a cave that can kill even the best divers? NARRATOR: Diving in Tham Luang
had already taken one life. It was an even greater
threat to children who had never dived before. But the greatest danger of
all, lay not in the cave, but in the heads of
the boys themselves. MARTYN: If you take
an inexperienced
person underwater then there is a high probability
that they're going to panic. How were they going to cope
with something as traumatic as the prospect of diving,
where you can't see your hand in front of your face? JASON: If they'd have panicked
underwater they could have not only killed themselves,
they could have dragged our regulators out of our mouths
we didn't want them to die and we didn't want
to die ourselves. NARRATOR: So the divers
made the most radical
decision of the rescue. To sedate the children. JASON: It was a consensus
amongst all the divers. We weren't going to risk doing
it without them being sedated. NARRATOR: Doctors tailored a
different mix of anesthetics for every child, depending
on age and weight. No one had ever attempted
to dive with unconscious
children before. MARTYN: Having to sedate these
youngsters to such a level that they were incapacitated
but remain alive, and then be thrust into
the cold water was an extremely risky proposition. JASON: As we were planning
it we were thinking, you know it could be some of
these kids that are gonna die. NARRATOR: And as our
cave data reveal, using a sedative left
the cave divers with a further complication. To extract each boy
through the five sumps would take three to five hours. But a safe dose of the
sedative would last
just an hour or less. And so, to prevent
the boys from waking, the divers would
have no option, they'd have to inject
them during the rescue. JASON: Never actually
done it before and yes
it was the first time. I was quite nervous obviously. NARRATOR: And they could
do that only in the dry
parts of the cave, between sumps,
not underwater... Something that would bring
diver Jason Mallinson
close to disaster. Nature was not on
the rescuer's side. More rain was forecast. PASAKORN: If we didn't rescue
them immediately we might have had even bigger problems. NARRATOR: They scheduled
the extraction. NARRATOR: As more
monsoon rain closed in, the divers headed
inside Tham Luang. The boys had been
underground for 16 days. The most dangerous cave
diving rescue in history
was about to begin... VERN: We honestly
believed that there would
be an attrition rate, if two of them came out
alive that would've been a good result. NARRATOR: And the
world was watching. The rescuers began
their dive to Chamber 9. Jason Mallinson volunteered
to run the first rescue. The life in his hands was
14 year old Prachak Sutham, nicknamed Note. JASON: Until that first
flooded section was traversed by myself and the boy, nothing
else could move forward NARRATOR: Together they
would discover if a
rescue was possible. They fitted a single air tank
to Note's chest and gave him a buoyancy vest with
straps for Jason to hold. In case contact was lost,
a safety tether joined
boy to rescuer. To stop Note's mask
being dislodged, Jason would shield the boy's
head with his own body and finally, for both their sakes,
Note's hands were tied to his sides in case he awoke. Around 1 PM Jason and Note
began the first journey out. With the cave data
we can do something
impossible up to now. Use technology to see through
the muddy water to relive the most dangerous cave
diving rescue of all time. And reveal Tham Luang in
a way that even the divers were unable to see. This, the first sump, 1,000
feet long, underwater. And the dive line their
only chance of finding
their way to safety. JASON: The worst fear was
losing contact with the guideline and losing
contact with the boy. We felt a tremendous amount of
responsibility for the boys, a child's life that's in your
hands, a child who's asleep, a child underwater. I was nervous a
lot of the time. NARRATOR: At half
hour intervals, three more divers
entered the first sump
with three more boys. Not far behind
Jason and Note, were diver Chris Jewell
and 15 year old Nick. Separately each pair
approached Tham Luang's
first constriction. JASON: First time you
know about it is when
you hit the roof. NARRATOR: A low passage,
just 30 inches high, little room for error. CHRIS: My back would be
against the cave roof and my chest would be against
the floor of the cave. NARRATOR: The dive line was
difficult to follow as it meandered between
the cave walls. CHRIS: I was often bouncing
off the rock and having to kind of back up and try
and go forward again
into different spaces. NARRATOR: One after the other
the divers felt their way through the sumps carrying
their precious cargo. CHRIS: We might knock the mask
off so we were trying to go through these small spaces
quite carefully, taking our time whilst holding onto the
dive line in one hand and holding onto the
child in the other hand. NARRATOR: But the sedatives
were beginning to wear off. Making an already difficult
situation, life-threatening. JASON: You'd be diving along
underwater and you could feel
the hands twitching. NARRATOR: Revealed
accurately; the scene of
one perilous incident. Between dives, Jason
was able to surface, but he was still
chest deep in water. JASON: I was in a deep canal;
I was on my own and there was no dry place to put the boy
and I needed to inject the sedative into his thigh. NARRATOR: Ahead of them,
the second sump, another
1,000 feet underwater, Jason had no option but
to inject the sedative right where he was. JASON: I was trying to undo
the dry bag with two hands but keep control of
the child as well. It was quite hard to hold
him I had to sort of pin him against the wall with my leg,
try and get all the syringes out of the bag, they all
started floating around in the water and I'm trying to
get the, the syringes. I was quite nervous obviously, and I managed to
bring his leg up, put the sedative
into his leg. MARTYN: The whole thing
is really fraught with
mental strain. JASON: High stress,
that's for sure. NARRATOR: After
two grueling hours, rescuers and boys had
traveled through four sumps along a mile of cave. But it wasn't over. Ahead lay a dive in the
final sump and the tightest
squeeze of them all. NARRATOR: Following the dive
line the survey team locates Tham Luang's
worst pinch point. ROO: Look at this
constriction. MAN: Doesn't look very nice. ROO: Gosh that's small. NARRATOR: How would a diver
and a child fit through here? The 3D data exposes
the problem, over 100 feet into
the final sump. The dive line goes through
a curtain of stalactites. A gap just 20 inches wide
at its narrowest point. JASON: You couldn't fit
through the stalactites. It's certainly the
most difficult part of
the cave to navigate. NARRATOR: But the data
reveals something the
divers couldn't see. Below the dive line, a
wider passage, 6 feet deep. But making use of this space,
by feeling a way through, was risky. CHRIS: You have to back out,
pull the line and find the biggest space that you
could work your way round. JASON: We had to
pull the line down, stretch it down and go
under the stalactites. NARRATOR: By pulling down on
the dive line the divers could swim beneath the pinch point. But the extra tension
on the line made it
harder to hold on to. JASON: There was always
potential for it to slip through your fingers and
then spring up into the roof. NARRATOR: Slowly
and carefully, the divers made it through
without losing the line, this time. By late afternoon Jason
had been caving and diving for five hours. Awaiting them in Chamber 3,
the international rescue team. JASON: You just knew that
you were seconds away from surfacing and being able to
pass responsibility for that boy's life on to
somebody else. JOSH: The cave line would start
to get some tension on it, like a fishing line and
so the guys in Chamber 3 would radio up 'fish on'
because that meant a diver was pulling on the line,
coming toward them. JASON: I was very
relieved to have got
that first boy out alive. NARRATOR: Expert cavers
and medics took over. They carried and hoisted Note
in a stretcher through the final half mile of cave. The first four boys were
out of Tham Luang cave. All alive. REPORTER (over TV): Mission
impossible has now become mission incredible. REPORTER (over TV): Well this
is what all of those who've been involved in this operation
have been waiting to see, the boys are coming out. CHRIS: The buzz was amazing. It was quite incredible that
we got the first four out we weren't sure we would. VERN: Emotions were
running high, um, as you can probably tell,
now, um, absolutely amazing. NARRATOR: Eight more children
and the coach remained inside. A further energy-sapping 8
hours of diving and caving for each rescuer, lay ahead. CHRIS: We needed to do it not
once more, but twice more. NARRATOR: The divers
headed back for a
second group of boys. It was another success. REPORTER (over TV): Four
more boys emerging from that cramped and flooded cave. REPORTER (over TV): All
are now in hospital in
nearby Chiang Rai... NARRATOR: There were
just four boys and the
coach left to rescue. But the drama was
far from over. Chris Jewell was diving
out with the 11th boy, 13 year old Sompong Jaiwong. JOSH: It's very easy to
forget the 11th dive is as dangerous as the 1st dive. NARRATOR: Two hours in,
Chris entered the last sump. CHRIS: I had the last
bit of diving to do. I thought I'd sussed it. NARRATOR: The 3D data
reveals the dive line
goes around a corner, where it is pulled
tight beneath a boulder. For Chris, the tension on
the line proved too much. CHRIS: Through the process of
going round that corner I was stretching the line with my
hand and it just slipped out of my fingers. When you lose the line
in an underwater cave that's really bad news. I couldn't see
which way to go. NARRATOR: Time
was running out, both Chris and the
sedated boy were using up their limited air supply. CHRIS: I was sweeping with my
arms, trying to pick up the line and I couldn't find the line. The most important
thing is not to panic. NARRATOR: The data reveals that
as Chris felt for the line it lay just within arm's reach, but in zero visibility, finding it was a
matter of chance. After 4 long minutes, Chris
discovered not the line, but an electrical cable, laid in the early
days of the rescue. Instead of leading Chris out,
it led him all the way back, to the start of the sump. CHRIS: Thankfully I realized
I was back somewhere that I was familiar with. NARRATOR: In the dry cave
Chris found the line and continued his rescue. Against all the odds, the rescuers completed
their mission. ITN: They are safe, they
are out, they have done it! REPORTER (over TV):
They have been rescued
from that flooded cave. REPORTER (over TV):
Millions of people are
breathing easier tonight. NARRATOR: After an intense
struggle with nature. The agonizing wait was over. VERN: Unreal,
amazing, 13 out of 13, it's not an unlucky
number anymore. CHRIS: Things that seem
impossible aren't always so. Difficult things can be achieved
and amazing things can happen. PASAKORN: None of us were
doing this out of duty but out of a desire
to save them. ROO: I remain in absolute awe
of everybody that took part and the wonderful
story that this is. NARRATOR: Three months
later, on British TV, divers Chris and Jason
were reunited with the boys whose lives they'd saved. JASON: I didn't know
any of their names. I remembered them by
numbers 1, 5, 9, and 13. (applause). I think they really wanted to
connect with the people that had brought them out so
it was a really nice, nice thing that. TRANSLATOR: You are my heroes, thank you very much from
the bottom of our hearts. We love you. (applause).
