'It's My Party' singer Jessie proudly wore a 'Philly' T-shirt dress as she belted out her hits at Q102's Jingle Ball on Wednesday night (10 December).
The former Voice UK judge completed her outfit wearing thigh-high leather boots and pranced around on stage as she entertained the crowd.
One word: Fierce!
Jessie wasn't alone though, as she was soon joined by her recent collaborator Ariana Grande, to perform their chart-topping single 'Bang Bang'.
The girls - along with Nicki Minaj - achieved huge success with 'Bang Bang', as the uptempo track got to Number One in the UK and was a Top 10 single in America, Australia and across Europe.
Over the weekend, Jessie, who is dating US R&B singer-songwriter Luke James, took to the stage at the Capital Jingle Bell Ball, which was held at London's O2 Arena.
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Watch Jessie, Ariana and Nicki's video for 'Bang Bang' below: