In 2010 Darius won Popstar to Operastar. The show began on 15th January and finished on 19th February.
It was a reality TV music competition which showed 8 professional pop singers training to be an opera singer under the tutelage of mentors Katherine Jenkins and Rolando Villazón. 

On each live programme, each popstar performed an operatic aria, after which the judging panel, consisting of the two mentors alongside Meat Loaf and Laurence Llewelyn-Bowen gave their verdict on the performance.
After all of the popstars have performed, the phone lines were opened for the public to vote for who they wanted to see progress to the following week's programme. Following a well-trodden format, the two popstars that received the fewest public votes must sing again, before one of them was eliminated by the judges. The field was narrowed over several weeks, before two popstars were eliminated in the semi-final, leaving just Darius and Bernie Nolan to battle it out in the final for the chance to be declared the winner.

The contestants were: Darius Campbell , Alex James, Marcella Detroit, Vanessa White, Bernie Nolan, Kym Marsh, Danny Jones and Jimmy Osmond.

During an interview in 2010 Darius said that appearing on Popstar to Operastar felt like coming home. “It really appealed because my parents are huge opera fans. I fell in love with opera at a very young age because my dad always played it in the car.” As a youngster, Darius dabbled in the world of opera when he appeared in the Scottish Opera production of The Trojans.

From there he had to decide whether or not to pursue a career in opera – but finally decided to go to university instead. Little did he know he’d get the opportunity to revisit his old dream, thanks to Popstar to Operastar. “It’s been a shock to find there’s a world of technique and military discipline and work ethic out there that exceeds anything in pop,” he said. 

Darius performed the following songs during the competition:
Week 1: Nessun Dorma
Week 2: Toreador Song
Week 3: Granada
Week 4: Non Piu Andrai
Week 5: Fin Ch'Han Dal Fino 
Week 6: Non Piu Andrai, Dream The Impossible Dream and Brindisi

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Following his duet of Dream The Impossible Dream with Rolando Villazón during the final, Darius told the audience;
"I just found out today that, ten years ago, I had my first ever final in this very studio in Popstars. Then I had my second final, four years later.
'It's been an honour to perform here in front of my family. That was a dream come true."
Darius was declared the winner with 50.1% of the public votes and closed the show with a rendition of Non piú andrai.