The British actress impressed us yesterday with her raspberry hued lip and chic French bun combo and she has shown off her fashion credentials on day two of the annual film festival in this off the shoulder number.
The blonde beauty was spotted wearing the uber stylish dress which boasted a sequin bustier and skirt, a studded waist cincing corset and a neckline consisting of hundreds of linked metal chains.
Sienna teamed the figure hugging dress with a pair of black stiletto sandals complete with ankle strap detail - good choice!
She cut a glam figure in the original dress as she posed for a series of pictures with celebrity friends at the Cannes get together and was seen sharing a laugh with actor pal Jake Gyllenhaal, too.
Sienna looked every inch the 50s siren with her short hair which was blowdried and rollered to perfection but she decided to swap yesterday's just bitten lip for a mauve shade that accentuated her already plump pout.
Luckily for you, we've found a super similar match in Topshop's Devotion Lipstick and for a purse friendly £8 you can afford to stock up for summer!
The stunner has totally nailed Cannes chic so far but we can't wait to see what else Sienna wears this week, and as always, we're keeping our fashion forward eyes peeled!
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