The former Big Brother star was snapped outside the exclusive Sanderson Hotel in London with a pal and looked hot to trot in her traffic-stopping number.
Imogen's bright red frock was made of lace with cute little cap sleeves, and she teamed it with a pair of peep-toe black Louboutins.
The mum-of-one styled her brunette hair into glossy waves, added a slick of pale pink lipstick and some oomph with smokey eyes. Gorgeous!
Before heading out, Imogen had posed for a selfie, which she then shared on Instagram. Commenting on the picture, she said: "On my way to the Sanderson hotel! All about red lace....#debra #red #w1 #event #london."
Imogen, who is mum to daughter Ariana Siena, also took to Twitter following her night out at the Izabelle Hammon press launch and told her followers: "Hahahaha! So much fun @uzbeautyldn #sanderson #tipsy #pics #lettinghairdown #fun #nightoff."
It's good to see Imogen letting her hair down, as she is rarely seen without daughter Ariana by her side. Earlier this week, Imogen was spotted with Ariana in Chelsea while filming for BBC Wales.
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