Donning a pair of bright hareem pants and a matching cropped blazer jacket, the judge almost stole the show in her one-of-a-kind outfit.
The star paired the electric number with a strappy black bralet with black heels and wore her hair in a beautiful braided bun.
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Since BGT returned to air, Alesha has certainly upped the ante with her beautiful outfits.
For last week's show, the singer dazzled in a gorgeous rainbow-hued dress from Rami Kadi, commanding attention in the strapless sequinned number.
But even more spectacular was the doting mum's eye-popping jewellery!
The TV favourite completed her look with a few choice Veiled Rebel pieces, proudly showing her support to a black-owned brand in the midst of the Black Lives Matter movement.
Alesha looked sensational for the first semi-final
The company, founded by solicitor-turned-designer Alison Morris, prides itself with creating "unapologetic unisex jewellery".
They combine new technology and traditional techniques to produce jewellery with a minimal aesthetic - and we love that Alesha has put the spotlight on an independent brand.
Alesha wore beautiful jewellery on last week's show
Alesha opted for the 'Duo Claw Maxi Earrings', which retail at £165 and were perfectly complemented by the £245 'Claw Maxi Ring'.
The totally unique designs added a rock chic edge to her fairytale dress.
Founder Alison took to Instagram at the time to share some stunning behind-the-scenes shots of Alesha, thanking stylist Laury Smith and writing: "An incredible night. @aleshaofficial on @bgt semi final show wearing our duo claw maxi earrings and claw maxi ring. Looking absolutely stunning".
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