The head-judge jumped up to demonstrate her Latin skills when discussing key moves from a Salsa.
Pairing up with professional dancer Kevin Clifton, the 57-year-old performed an impromptu routine while host Zoe Ball looked on in awe.
However, during a spin, she flashed her knickers when her golden dress lifted extravagantly.
Despite the wardrobe malfunction, viewers of the Strictly Come Dancing spin-off show were loving Shirley's appearance, flocking to Twitter to discuss her moves.
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Shirley flashed her knickers during the impromptu performance
Shirley showed off her skills and her underwear in the performance
One posted: "OMG Shirley is such a Queen. What did we do to deserve her?!"
Another added: "Wow….loving @ShirleyBallas & @keviclifton dancing together on #ItTakesTwo."
A third gushed: "@ShirleyBallas you were AMAZING dancing on #ItTakesTwo this evening with Kevin. Wonderful judge!"
Strictly Come Dancing judge Shirley Ballas
Sat, September 16, 2017
Shirley Ballas is the new head judge for the 2017 series of Strictly Come Dancing, replacing Len Goodman.
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Strictly Come Dancing new head judge Shirley Ballas
Shirley has found herself under fire recently as she clashed with Brendan Cole over the criticism she gave Charlotte Hawkins last week.
The pair found themselves arguing over rise and fall in a Tango on Saturday's show and the debate has bubbled on throughout the week.
Strictly Come Dancing continues tomorrow on BBC One at 6.45pm.