The supermodel stepped out at the LACMA: Art and Film Gala in Los Angeles on Saturday (2 November) wearing a dark purple floor-length number by Gucci.
Rosie is well known for turning heads, but this time she caught attention for all the wrong reasons!
Her designer frock featured a daring plunging neckline and a rather shapeless silhouette, which drowned her slender figure.
We're not keen on the sequin embellishment either, which formed an odd pattern across her chest and hips.
She let her extravagant dress take centre stage by keeping jewellery to a minimum, adding a chunky cuff and dainty earrings.
Luckily the actress got things right in the beauty department with sunkissed cheeks, shimmery champagne lids and fluttery lashes.
Fab make-up Rosie, just ditch the odd frock next time!
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