The singer took the plunge in a revealing red number as she attended the AQ/AQ Relaunch Party in London.
Aside from showing off a healthy dollop of side boob, Mollie was looking tanned and toned, having just returned from a break in America.
The star was making us all jealous with a series of holiday snaps, where she revealed her enviable bikini body.
Mollie also recently revealed that she is penning her first book.
She told Hello magazine of the project earlier this month: "It's a novel and it's very early days, but it's an idea I had and I'm really excited it's happening".