The 41-year-old actress and TV personality flashed her black bra in the see-through shirt teamed with the skirt and a pair of black heels as she graced the soggy Union Jack carpet at the Palladium.
Hot on Holden's heels was Alesha Dixon, injecting some colour in a coral-coloured blazer, matching skirt and white shirt.
It is currently being reported that fellow Britain's Got Talent judges David Walliams and Simon Cowell are constantly bickering and criticising one another during the auditions, despite their blossoming "bromance" on the talent show last year.
A source told Digital Spy: "Walliams was continually winding up Cowell with his gags, but unlike last year, the big boss wasn't finding them funny.
"The bromance appears to be over and the audience and acts could see tension growing between the pair."
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