The Brit model displayed her absolutely perfect pins in the ensemble which boasted a gorgeous flamed hemline, hundreds of multicoloured, mirrored sequins and a plunging vest top.
The stunner opted to team the glitzy outfit with a white diamond choker and pair of black pointed Louboutin courts, although it looks like they might have got a bit lost on the carpet!
Rosie chose to let the embellished getup do all of the talking as she wore her new bob tresses, cut by celebrity hairstylist and bestie George Northwood, in undone waves with a bit of volume at the crown - beautiful!
When it came to her make-up, Rosie totally rocked beach babe glam. We love her heavily bronzed look!
The leggy blonde plays the role of Splendid and stars alongside Charlize Theron and Tom Hardy in the movie which lands in cinemas later this month.
For exclusive competitions and amazing prizes visit Reveal's Facebook page NOW!