We’re not sure what her Mean Girls character Regina George would say about it, but we absolutely loved Rachel McAdams’ look at the About Time world premiere at London’s Somerset House (yes, the official home of London Fashion Week!) last night.

The actress showed off a red hot new hair colour at the premiere, and also showcased her style credentials in a stunning long-sleeved Roksanda Ilincic Resort dress which came complete with a futuristic belt at the waist.

Rachel has a figure to die for so we would have forgiven her for wearing something skimpier to show off her body, but we thought her outfit choice showed off so much more. And that’s her maturity, her versatility and her ever-growing status as a style maven.

We love it – what a perfect outfit to wear at one of the most fashionable locations in London!