David Walliams responds with particular enthusiasm to Soran and Bradley, who give an erotic ballroom twist to uplifting tune 'You Raise Me Up'.
"As soon as you started dancing, your love for dancing and love for each other really came across and it was really truly moving," the Little Britain comic said after the pair performed.
Fellow panellist Amanda Holden gushed: "It was a really courageous piece and I found it absolutely beautiful and inspiring - congratulations! Brilliant."
Meanwhile, Alesha Dixon exclaimed: "That was a real love story, I just fell in love with you; you dance beautifully together. Honestly I've never seen it before and I would love to see it again. Well done."
Simon Cowell was the only judge unconvinced by the act, claiming that one of the pair "nearly fell over".
Britain's Got Talent returns for its sixth series tonight at 8pm on ITV1.
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Watch Simon Cowell talking to Digital Spy about the new series of Britain's Got Talent below: