As Darius Danesh, he wowed telly audiences in the early Noughties by battling his way to the last three of ITV singing show Pop Idol.
But the Scottish entertainer – now known as Darius Campbell – found himself in a much more serious fight after a video shoot for the charity he supports went horribly wrong.
In the terrifying 2015 ordeal, Darius, now 37, had to be rushed to hospital after drinking dirty water from the River Thames.
And he’s now revealed that it was touch and go whether he’d survive, after he slipped into a coma with his brain swelling to dangerous proportions.
Darius is an ambassador for the non-profit organisation Fresh2O, and was shooting a demo video for its new water filter.
The device is said to remove 99.9 per cent of known water-borne pathogens, bacteria and viruses.
To prove its effectiveness, the singer tried it out by sipping water from a Thames sewage outlet. But shortly after, he started to feel very unwell.
He told the Daily Record: “I drank the water for the video and raised the funds but, when I went to Glasgow to see my mum for her birthday, I collapsed.”
Read more: Robbie Williams opens up about ‘confusing’ health scare that landed him in intensive care
His father rushed him to hospital, where it was discovered that he’d contracted an inflammatory virus that made his brain swell to a size bigger than his skull.
It turned out that he’d accidentally drunk from a water bottle containing the WRONG anti-viral filter.
Darius slipped into a coma, and when he finally woke up, his mother was there to greet him at the side of his hospital bed.
For the singer, that was a very strange experience, as she was being treated for breast cancer at the time, and yet here she was holding a vigil at HIS bedside.
“It felt upside down and wrong because my mum was going through cancer treatment,” he explained. “Yet she was next to me with tears in her eyes, telling my brother that they almost lost me.”
Read more: Cheryl and Liam’s dream Christmas hit by rumours about his workload
Darius – who finished third in the first series of Pop Idol and also took part in Popstars – was bed-bound for three months but managed to pull through (his mum recovered, too).
And although his ordeal was terrifying, he’s adamant that some good came out of it.
He said: “In an inadvertent way, I proved the water filter worked, because the others who drank from a bottle with [the correct] filter in it didn’t get sick.”