For the heroic British divers who found a missing Thai football team in a flooded cave system, it was only the latest in a series of brave rescue missions around the globe.
Rick Stanton, 56, and 47-year-old John Volanthen had been called in by the Thai authorities last week along with fellow British caving experts Robert Harper, from Somerset, and Vern Unsworth.
The UK divers who reached the stranded group that had been missing for nine days were described as the "A Team" by Bill Whitehouse, vice chairman of the British Cave Rescue Council.
He told Radio 4's Today programme: "They are really the sort of A-Team, if you like. They have been at the spearhead of making their way through because they have the skills and expertise to do it.
"One of the first things they had to do in pushing through is lay a guideline so that they could get out again and so others could follow along."
Voices heard on a video of the moment the group was discovered in the cave belong to Mr Stanton and Mr Volanthen.
Video: The moment UK divers found trapped group
The pair have established a reputation as being among the greatest cave rescue divers on the planet - but both have day jobs in the UK.
Mr Stanton has been a firefighter in Coventry for quarter of a century, while Mr Volanthen is an IT consultant based in Bristol.
Both are volunteers with the South and Mid Wales Cave Rescue Team.
In 2011, the pair set a world record for the longest cave dive, penetrating 9km (5.5 miles) down a system in northern Spain using specially developed equipment.
John Volanthen: IT engineer who took up diving as a Boy Scout
John Volanthen, an IT consultant based in Bristol, took up diving as a Boy Scout and studied electronics at De Montfort University, Leicester.
When not diving, he spends his spare time running ultra-marathons of up to 153 miles.
It was Mr Volanthen's voice that was heard on a video released by the Thai government, asking the footballers "How many of you? Thirteen? Brilliant."
He has described himself as the opposite of an adrenaline junkie.
"Panic and adrenaline are great in certain situations, but not in cave-diving," he told a newspaper at the time.
"The last thing you want is any adrenaline whatsoever. You’re in an environment that doesn’t suffer fools gladly.
"I enjoy the logistical challenge, getting us and all our kit to the end of such a long cave. It’s like that puzzle with the fox, the chicken and the grain.
"It’s not dangerous if you do it right - there are just a large number of little things that you have to be on top of at all times."
Mr Volanthen, originally from Brighton, attended Westminster University and has worked in Bristol for the past 20 years, according to his LinkedIn page.
He told the Sunday Times magazine in 2013: "If something goes wrong 10 kilometres down an underwater tunnel, you usually have until your air runs out to find a solution or make your peace."
Rick Stanton: Firefighter inspired by TV show to explore caves
With Mr Volanthen was Rick Stanton, who began diving aged 18 to explore caves after being inspired by a television programme.
Mr Stanton - a firefighter from Coventry, West Midlands - was awarded an MBE for his rescue work in 2013.
At the time, he said: "When I got notification of this on behalf of the Palace I was absolutely astounded. I’m just doing work I enjoy to the best of my ability."
One of Mr Stanton's neighbours in Coventry told The Telegraph: "I don't know too much about him as he's always away - probably going on dives I think.
"I'm not sure how long he's been diving, but when I heard what he had done I thought it was quite incredible."
Another said: "I actually don't know him, but now I might have to go round and congratulate him when he's back."
Neighbour Tina O'Brien, a 65-year-old legal personal assistant, said: "He's been a person who travels a lot. He used to do potholing before he got into diving so that's probably why he was so good in the cave.
"He's a very calm person, quite quiet. He has lived here for a long time."
Ex-serviceman Ray Reid, who has known Mr Stanton for a number of years, said: "He certainly has the expertise and skills.
"He's a very down-to-earth guy - doesn't look like your typical action hero."
His MBE was partly for his efforts, along with Mr Volanthen, in attempting to rescue French potholer Eric Establie, who got trapped in the Draggonniere Gaude cave system, in the Ardeche region, in 2010.
Mr Establie, who was known by both divers, had become trapped by a silt avalanche nearly a kilometre into a dark, water-filled tunnel.
Only a handful of rescue divers in the world had the expertise to find him and the British pair were flown in on an RAF helicopter
Working in visibility of less than a foot, they managed to find the blockage in the tunnel, get through it and locate the potholer's body.
At the time, Mr Volanthen said: "Eric would have done the same for us, so there was never any question of us not going."
Both men were awarded a bronze medal from the Royal Humane Society in recognition of their rescue attempt in the Ardeche Gorge, southern France.
Mr Stanton was also involved in a high profile rescue of British cavers in Mexico in 2004. He and other divers reached British servicemen who had been trapped by flooding inside the Alpazat cavern system in the Central American jungle.
The rescuers led them out one by one after equipping them with scuba gear, a process that took six hours.
He told the Coventry Telegraph at the time: "My biggest achievement was helping rescue the six soldiers. They were trapped for nine days and we had to teach a few of them to dive through a considerable length of passage to get them out."
Regarded as one of the world's leading cave rescue experts, he told publication Divernet that diving is a "hobby" he does voluntarily.
'We've got a job to do': Staying out of limelight despite heroics
Mr Stanton occasionally gives technical lectures about diving, but he and Mr Volanthen have generally remained out of the limelight despite their heroics.
As they entered the Tham Luang caves in Thaland to look for the missing football team, Mr Volanthen summed up their approach.
"We've got a job to do," he said, before disappearing into the darkness.
Celebrations quickly turn to challenges ahead
Bill Whitehouse, vice chairman of the British Cave Rescue Council, said he had expected the Britons to reach the group first as they were by far the most experienced involved in the search.
But he said some of the hardest work was still to come as they coordinated a dangerous rescue.
“The were doing the push-ahead and laying down the guidelines for others to follow,” he said.
“It is completely restricted with very dark tunnels and poor conditions, mud banks and areas that need excavating. They pushed forward on each dive, laying line and clearing the way.
“The Seals were following leaving dumps of air bottles in preparation for a rescue operation.”
Mr Whitehouse said that when the Brits arrived last week they did a couple of recce dives to assess the situation.
But conditions rapidly and “cataclysmically” worsened over the weekend as bad weather meant rising water and a strong current before the rain eased off and diving could begin again.
He added: “Diving them out will not be an easy process. It is difficult enough with just one person but when you have several terrified children who are not divers.. It will take a lot of planning, a lot of equipment and a lot of preparation.”
Mr Whitehouse described how celebrations on Monday that the group had been found quickly turned to the challenge ahead.
"It was euphoria for a moment and then you draw back and think 'what do we do' - it's not going to be easy to get 13 people out of a flooded cave," he said.
"There's space to make your way through, but it is 50/50 underwater over 1.5km (0.9mi). That's still a lot of diving and it's possible it will need a lot of equipment. The questions is how much time until the water goes up again."
Video: What Will It Take to Get Soccer Team Out of Thailand Cave?