If someone was to ask Margot Robbie if blondes have more fun, she’d now be able to give an informed decision. This year the actress, who made her name starring alongside Leonardo DiCaprio in The Wolf of Wall Street, has dyed her tresses from blonde to brunette and now she’s debuted a new copper-coloured do.

Margot RobbieMargot Robbie, debuting her new hair

23-year-old Robbie stepped out at the Natural History Museum in London to attend the One For The Boys male cancer foundation charity fashion ball. The event is just one of several which have taken place throughout the year to raise awareness and funds for cancers which affect men. The ball began with a champagne reception, which was followed by dinner prepared by Michelin star chefs, an auction and a fashion show.

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Robbie wore a stunning blue and white tiered gown, which she teamed with two-part strappy white sandals and a navy blue clutch bag.  She opted for simple makeup just applying a touch of nude lipgloss.  The demure but understated look meant that her new hair colour took centre stage and the actress looked calm and confident with her new flame red hair.

Margot RobbieMargot Robbie at the event in London today

Since her huge success in The Wolf of Wall Street, Australian-born Robbie has several big projects in the pipelines. She will be starring alongside True Blood Alexander Skarsgard in a 3D version of Tarzan due to be released in 2016. Later this year she’ll be back on the big screen in Focus with Will Smith, in a role that was originally pegged to go to Kristen Stewart.

Robbie was just one of the big name stars who attended the charity ball, which was also attended by singer Pixie Lott, comedian Simon Pegg and model David Gandy.

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Holly ValanceHolly Valance was at the event too

David Gandy
As was David Gandy