"How many of you?" asks the British voice loudly, a torchlight scanning the gaunt, hungry boys crowded on a muddy bank.
"Thirteen?.... Brilliant" -- a remarkable short exchange captured on video has electrified Thailand and paved the way for an astonishing rescue.
The video, which captures the twelve dishevelled and emaciated boys and their football coach sheltering on a slope in the pitch-black belly of a flooded Thai cave, was posted on the official Facebook page of the Thai Navy SEAL early on Tuesday.
The footage starts with a touching chorus of "thank you" from the boys, as the rescuers wade through the mucky water towards them.
Some have their red football shirts pulled low over bare knees to keep out the cold -- a sign of their unreadiness for nine days in the Tham Luang cave complex.
The conversation continues with murmurs of Thai as the group confers, punctuated by reassurances from the diver.
One boy asks in halting English if they will "go outside".
"No, no, not today... there's two of us, you have to dive... we are coming, it's ok. Many people are coming, many, many people, we are the first... many people come."
The diver gives the boys an extra light as the camera jags around and the audio fails, but steadies as one of the boys says "I am very happy."
"Thank you so much," say the boys, unfailingly polite despite the urgency of their situation.
They are from the "Wild Boar" football team and the first visual evidence of their survival lit up a country that has followed every permutation of a painstaking rescue that at times looked forlorn with floods rushing through the winding tunnels.
A three-member British team -- Robert Harper, Richard Stanton and John Volanthen -- arrived in Thailand last Wednesday to aid the search.
Two of the Brits reached the boys late Monday, sparking joy in a country that has held its breath throughout the agonising rescue efforts.
It was not immediately clear which diver speaks on camera. The team has avoided media all week, with Volanthen telling reporters only: "We've got a job to do" when he arrived at the site.
Social media in Thailand erupted following the news the boys were alive and safe and "13 lives survive" was the top Thai Twitter hashtag on Tuesday.
"I am almost in tears, you're so brave and tough," Facebook user Pharanya Suntaranusorn wrote under the video.
Elation at the survival of the group was tempered by the reality of a difficult extraction ahead and the possibility of psychological damage from the trauma of being trapped in the dark bowels of a mountain for a prolonged period.
"It's hard to tell (the state of their mental health) from the clip," said Wimonrat Wanpen, spokesperson from the Mental Health Department of the Public Health Ministry.
"Their lives are getting much better after several days of crisis... but whether they will develop trauma depends on many factors."
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
7 Killed, 3 Injured As Taxi Falls Into Roadside Well In Maharashtra: Report Watch: Inside Derailed Coaches, Rescue Teams Crawl In Search Of Survivors US Cop Who Laughed After Indian Student Jaahnavi Kandula's Death Fired World's Largest Isolated Tribe Makes Rare Appearance In New Footage Barack Obama Wants Joe Biden To Pull Out Of US Presidential Race: Report 32 Dead In Bangladesh Unrest, Protesters Set Fire To State TV Headquarters NEET PG 2024: Test Cities Out For Postgraduate Medical Entrance Exam After 53 Years, Mortar Shells From 1971 Indo-Pak War Found In Fish Pond "Humanitarian Crisis Due To Israel-Hamas Conflict Concerning": India At UN Track Latest News Live on NDTV.com and get news updates from India and around the world.