VERNON Unsworth claimed billionaire Elon Musk's tweets "humiliated" him before suing him for defamation.
But who is the cave diver? And what happened between him and Elon Musk? Here's everything we know.
Who is Vernon Unsworth?
Vernon Unsworth is a 63-year-old financial broker from St Albans, Herts.
He discovered his love for exploring cave systems in the Yorkshire Dales.
The experienced Brit caver now lives in Chiang Rai, Thailand, with his girlfriend, splitting his time between Asia and St.Albans.
Before the Thai rescue operation, he had been in a number of rescue efforts in the UK, but "nothing on this scale".
How was he involved in the Thailand cave rescue?
Mr Unsworth was the first foreign rescuer at the scene and played a crucial role in saving 12 Thai boys and their football coach.
He spent years exploring the Tham Luang cave system where the boys were trapped for 17 days — meaning he had expert knowledge that was vital to the rescue.
A number of British divers were the first to discover the desperate lads trapped 2.5miles down the Tham Luang cave system in Chiang Rai, Northern Thailand.
The boys, from the Wild Boars football club, got lost during a visit to the notorious tunnel network with their coach on June 23.
It was not until July 2, nine days later, that a massive search operation to track down the missing team ended in joy; they were all found alive.
Why is he suing Elon Musk for defamation?
Elon Musk branded Vernon Unsworth a "pedo guy" after he dismissed the Tesla businessman's idea to build a small submarine to help rescue the Thai cave boys.
Mr Unsworth blasted Musk's offer to help with the rescue as a "PR stunt".
When Mr Musk offered his help, he posted videos online demonstrating how "a tiny, kid-size submarine" could be used to save those stranded.
But Mr Unsworth said the businessman could "stick his submarine where it hurts".
In screenshots of a now-deleted tweet from Mr Musk's verified account, Musk said: "Sorry pedo guy, you really did ask for it."
The billionaire went on to claim he didn't see Mr Unsworth "at any point" during the rescue operation.
Then, at the end of August 2018 Musk bizarrely branded Vernon a "chid rapist" in an explosive email to a reporter.
The lawyer representing Unsworth has described the allegation as "completely false".
The outspoken tech CEO, 47, called Vernon a “child rapist” and claimed he moved to Thailand to find a child bride in a second baseless attack.
But on December 7 2019 Musk defeated the defamation claims.
Unsworth was seeking $190 million in damages for the shame and humiliation caused by the man his lawyer called a billionaire bully."