Simon Cowell transformed into Wicked witch for BGT

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Simon Cowell confessed he felt "slightly uncomfortable" seeing himself transformed into a green witch for the latest Britain's Got Talent semi-final.

BGT act RASK AI once again used artificial intelligence (AI) technology to appear as the judges singing a series of musical songs and pop hits. Cowell appeared as green witch Elphaba from the West End show Wicked, singing Defying Gravity. But despite admitting it felt strange to see himself perform on stage, Cowell hailed the AI camera act as "genius" and the best of the year.

What, how and why?

All the judges loved seeing their own image used as part of singing hologram act RASK AI. As in their audition the singers appeared live on stage and sang, but camera technology was used to superimpose the deep fake versions of the judges' faces onto them.

Bruno Tonioli's image was used to sing Supercalifragilistic from Mary Poppins, Alesha Dixon's AI fake sang Proud Mary as Tina Tina, Amanda Holden sang Dancing Queen from Abba with hosts Ant and Dec and Cowell was Elphaba from Wicked, singing Defying Gravity.

All the judges loved seeing themselves on stage and the act was a huge hit as far as they were concerned. In their original audition RASK AI had used the judges faces on characters from musical The Greatest Showman, singing uplifting tune This Is Me.

Holden told them: "Before you came on Alesha and I said you wont be able to do us again, but you did and it was even better. Especially for me as the biggest ABBA fan ever."

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Cowell said: "I've drawn the short straw... That was slightly uncomfortable at times, however I was asked this question earlier on about what makes a great audition and it is being unique and memorable.

"Something you're going to remember in a week, a month, a year. That was such a different level to what else we've seen so far tonight, it was brilliant It was genius and one of my fave live show performances of the year so far.

Some viewers were skeptical about the AI technology being used for the performance. While others spotted a likeness between Cowell and another TV judge and singer when painted green. Several said Cowell as Elphaba looked like Take That's Gary Barlow.

One wrote on social media platform X: "The Simon looks more like Gary Barlow #bgt #britainsgotalent" Another said: "Looks more like Gary Barlow #bgt"

What else happened on Britain's Got Talent?

But despite being a hit with the judges, RASK AI have not been voted through to the life final. The acts selected from the latest semi-final were Amanda Holden's Golden Buzzer act Sydnie Christmas.

The singer has faced a backlash from BGT viewers who complained the singer was professional, and not just a humble talent-show contestant. She trained at the D&B Academy of Performing Arts in London in 2014, has worked as a singer on cruise ships, performed in musical, had small parts in movies and even appeared in reality show Stage School.

Also voted through were comedian Mike Woodhams and singer Callum Scott.

Britain's Got Talent continues on ITV1 at 8pm on Thursday.