Darius Campbell Danesh: Simon Cowell and Gareth Gates lead tributes to late Pop Idol star

Cowell was a judge on the show on which Campbell Danesh finished third in 2002, behind Gareth Gates and winner Will Young in the inaugural series.

"I first saw Darius on television over 20 years ago and I got to know him really well," said Cowell.

"He was charismatic, funny and just a great person to be with."

Cowell added: "His passing, for someone so young, is an absolute tragedy and my heart goes out to his family and friends."

Simon Cowell - pictured in 2019 - was a judge on Pop Idol, the talent competition which saw Darius finished third

The cause of death is not known but his family said he was found in his US apartment.

Gareth Gates described Campbell Danesh as a "big brother" who "took me under his wing" during their time together on the show.

In a post on Instagram, he added: "He was one of the most beautiful, intelligent and gentle souls I was lucky enough to know, a soul that lit up every room."

Broadcaster Nicki Chapman, who was also a judge on the show, tweeted that Campbell Danesh was "a true gent with a kind soul and mischievous tinkle in his eye".

Campbell Danesh initially rose to fame on Pop Idol's ground-breaking predecessor Popstars on ITV in 2001, with his theatrical cover of Britney Spears' Baby One More Time.

Later that year, he resurfaced on the follow-up, Pop Idol, which concluded in 2002, minus his ponytail and beard and with a new attitude that took him to the last three. The final was watched by more than 13 million people.

Myleene Klass, Michelle Heaton and Jessica Pietersen, who also found fame on Popstars, in the bands Hear'Say and Liberty X, shared their memories of him.

Another former Pop Idol judge, Pete Waterman, told the BBC on Wednesday that Campbell Danesh, who left his pop career behind to star in musicals, sing opera and produce films, was a victim of his own talents.

"The truth was he never really achieved his potential because he really was larger than life, and he could have been Michael Buble if he'd chosen, if he'd stuck to singing he could've been enormous, he was so talented."

"If you stick to one thing and drive it you can become the best, but you can't be the best at everything.

"He was working on a major Hollywood movie when I had tea with him [recently], he was so excited."

The five Pop Idol finalists (left to right): Will Young, Zoe Birkett, Darius Danesh, Hayley Evetts and Gareth Gates

Reflecting on his career in an interview with Digital Spy in 2017, the performer said his early experiences on the shows helped to shape him.

"I look back at it all with fond memories, and with deep appreciation of the support of the British public at a time when I first went through Popstars - I made mistakes and I was too cocky and I didn't have humility," he said.

"I came back with a willingness to learn from my mistakes and to simply share my voice and love of music," he added. "I have deep respect for anyone who puts themselves in the position of being judged or being possibly put in the position of public criticism."

After impressing on Pop Idol, he turned down a record deal from judge Cowell in order to work with producer Steve Lillywhite, who collaborated with him on the pop hit Colourblind.

He later told The Guardian his reasons for turning down Cowell's "gracious" offer was that he had been encouraged to release two covers when we wanted to work on original material.

"Imagine, I could have done a cover of Gareth's cover of Robson and Jerome's cover of the Righteous Brothers," he joked. "How great! You know, that doesn't inspire me."

Campbell Danesh went on to enjoy four more UK top 10 singles over the next three years - Rushes, Incredible (What I Meant To Say), Kinda Love and Live Twice.

He then forged a successful stage career, appearing as Billy Flynn in two runs of Chicago, once claiming he based his portrayal of the scheming lawyer on Cowell.

Campbell Danesh pictured with his co-stars at the launch of Chicago in London in 2011

"He's the consummate businessman and a wonderful guy and there's a lot of Simon Cowell in Billy Flynn in terms of the way he approaches things, and I recognise that in terms of the character," he said.

He credited Cowell with persuading him to take on the role, opposite Ugly Betty star America Ferrera.

"I'm incredibly grateful for the experiences I've had and all the opportunities that it opened up and to be able to call Simon Cowell a friend and to be able to have dinner with him."

He featured in the Olivier Award-winning Guys and Dolls and played Rhett Butler in Sir Trevor Nunn's 2008 West End musical adaptation of Gone with the Wind.