The Saturdays singer kicked off her Monday afternoon (1 December) by heading to the mothers2mothers World AIDS Day VIP lunch at the Mondrian Hotel in London.
Opting for the androgynous look, Mollie kept things simple yet sophisticated in an all-black ensemble, wrapping up warm for her luncheon in a chunky black knit jumper.
Singer Mollie - who is signed to Next Model Management - added a pair of wide-leg tailored trousers which just skimmed her ankles, while giving her getup a feminine touch with towering court heels.
She held a large envelope clutch in one perfectly-manicured hand while leaving her golden blonde locks to drape past her shoulder in a tousled, beachy 'do.
But it wasn't long before Mols switched her demure outfit for something a whole lot sexier, pulling out all the stops while attending the British Fashion Awards 2014 later that evening.
The blonde bombshell wore a figure-hugging dress by Patricia Bonaldi which featured a nude mesh design which revealed more than a hint of her svelte silhouette, plus gold embroidery and delicate beadwork to cover her modesty.
She opted for strappy sandals (they're the 'Sophia' heels, £65 from Office) teamed with a glossy jet black pedicure, ditching the jewellery entirely while showcasing autumnal berry red nails.
And she certainly made a statement with her beauty look too, opting for a wet-look, slicked-back hairdo along with a flick of feline liner and vampy vino lipstick.
Other attendees at the lavish event included Rihanna, Victoria and David Beckham, Harry Styles and Kendall Jenner, plus Mollie's model boyfriend David Gandy (but they didn't pose on the red carpet together - boo!).
What do you think of Mollie's outfits? Let us know by commenting below as the best comment across the site each week wins £50!
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