Darius Campbell Danesh was seen with Hollywood friend Gerard Butler in a final photo taken of him before his tragic death.
The former Pop Idol star was found dead in his apartment in Minnesota on August 11, his family announced in a statement on Tuesday evening. His cause of death remains unknown.
In a final picture taken of Darius taken just weeks before he died, he was spotted going for a walk barefoot with the A-Lister near Gerard's Malibu home.
Wearing a flat cap and rolled up khaki trousers in the photo, which was taken on June 11, Darius walked a dog as he carried a pair of boots
In an emotional statement on Tuesday evening, his family wrote: "It is with great sadness that we announce the passing of Darius Campbell Danesh. Darius was found unresponsive in bed in his apartment room in Rochester, Minnesota, on August 11 and was pronounced dead in the afternoon by the local medical examiners' office.
"The local police department have confirmed that there were no signs of intent or suspicious circumstances. The cause of his sudden death is unknown at this stage while medical examinations continue.
"We ask that you kindly respect our wishes for privacy at this time whilst we come to terms with the tragic loss of our son and brother."
Devastated fans flocked to Twitter to pay tribute, with one writing: "I'm sorry but what in the name f*** is this?! Gutted, absolutely f***ing gutted."
While another commented: "Sad news this afternoon that Darius has passed away. Just heard this on @1025Clyde1 with @garry__spence Love to all his family x."
A third wrote: "Iconic. Colourblind was and still is a tune! RIP #darius #dariusdanesh."
Nicki Chapman was the first of the Popstars judges to share their heartbreak over his death, writing on social media: "There will only ever be one Darius Campbell Danesh.
"A true gent with a kind soul & mischievous tinkle in his eye. From that eventful first audition on Popstars to him kindly inviting me to see him perform on the West End stage.
"Thoughts are with his family at this sad time."
While X Factor alumni Rylan Clark tweeted: "Proper sad about Darius."
West End star Carrie Hope Fletcher commented: "This is such sad news” with a broken heart emoji.
The Scottish singer-songwriter and actor - who was known as Darius Danesh when he made his first bid for fame in ITV show Popstars in 2001 - also appeared on the first Pop Idol, which was won by Will Young.
After his successful stint in Pop Idol, he was offered a record deal by Simon Cowel l - which he turned down in favour of working with producer Steve Lillywhite.
He went on to forge a successful stage career, appearing in Chicago as Billy Flynn in two runs of the production, as well as Guys And Dolls, Gone With The Wind and more in the West End.
He lived in the US and found love with Canadian actress Natasha Henstridge, whose films include sci-fi hit Species.
The couple married in 2011 at the San Ysidro Ranch in Santa Barbara, California, but were divorced a few years later.
