The wedding party was laughing and joking as people put on their best smiles for the photographer, the next they were floundering in a muddy lake.
These astonishing images show the moment the wooden decking they were standing on gave way plunging the 80 smartly dressed guests into the water below, reports The Mail.
The bizarre dunking happened as bride Marli van der Walt, 34, and her new husband Hoffman, 38, gathered their extended families and friends at a South African beauty spot for a photo of their big day.
Hoffman's sister Alet told how the group excitedly posed for the picture before the deck collapsed.
She said: 'One minute we were all standing together waiting for the photograph to be taken and the next thing I knew I was underwater.
'It was pretty frightening at first - people tried to grab hold of each other for safety.
'Suddenly we were all in the water and it was just chaos.'
Bystanders dived into the lake to help after the incident, which happened at the Dragon Peaks hotel near Winterton in KwaZulu-Natal.
Afterwards, a soaked Hoffman could be seen wringing his socks while another guest's trousers were ripped revealing his underpants.
The bride's elderly mother, who was sitting in her wheelchair when the incident happened, ended up in the water as well as Marli's 88-year-old grandmother and a newborn baby.
Marli and Hoffman, who live in Durban, had chosen the resort's sturdy-looking 'entertainment' deck for their formal wedding photographs after they were married last week.
The scenic structure is in the middle of a picturesque dam and accessed by a wooden walkway.
But Alet said it started creaking as soon as the guests gathered for the photos.
Pictures show the group gathered moments before the decking collapsed and chronicle the chaotic aftermath as the guests thrash about in the water.
Alet added: 'They had wanted everyone on the decking because it was a lovely backdrop for the pictures, with the mountains behind.
'As we stood there was some joking about who was so big that they were making the deck creak, when the deck groaned again.
'The next moment the wooden struts decided they'd had enough and broke right behind where the bride and groom were standing.'
The bride's brother Hubert had been taking photos of the event but ditched his camera to dive in and help when the decking collapsed.
Miraculously only one guest was injured in the incident when his leg got splintered on a piece of wood.
The man, the bride's nephew, was later treated in hospital after his wound became infected.
Once the rescue mission was over hotel staff were sent to retrieve floating shoes, handbags and hats from water. The family said dozens of mobile phones, cameras and wallets were also fished out.
But incredibly the newlyweds seemed unperturbed.
Once everyone was back on dry land they asked the photographer to continue with the wedding portraits.
The bride stood patiently while her new sisters-in-law cleaned her muddied train with a fire hose.
And once the pictures had been taken the group tucked into their wedding dinner as planned.
Alet added: 'Once we knew everyone was OK we found it all quite funny.
'Hoffmann had to wring out his socks, and then he got the party started again.
'Some people were angry because their clothes were dirty and their cell phones or cameras had been broken but the bride and groom were determined not to let what had happened spoil their day so we just carried on like normal.
'Most of us were staying in the hotel so we went and changed.
'Some of the older guests were a bit shocked by it all but in the end it was a fantastic party.
'At least it means they'll have wedding photos they'll never forget.'
The wedding party has asked the hotel to replace their guests' property after the dunking and compensate them for damage to bride's mother's £1,800 electric wheelchair.
Hotel manager today Bithia Katz said she had apologised to the couple.
She added: 'The deck was quite new, certainly no more than five years old.
'It was designed to take a significant weight but clearly it became overloaded.
'It was unfortunate that this happened to a wedding party but luckily nobody was seriously hurt.
'Afterwards they all carried on as normal and enjoyed themselves.