The pop star attended Leonardo DiCaprio's fundraising gala for his self-titled foundation in St. Tropez on Wednesday.
Carey stole the spotlight wearing a plunging black gown, of course, accessorizing her look with plenty of diamonds. The blonde beauty attended the event with her fiance James Packer, though they arrived separately to the festivities.
The 46-year-old "Butterfly" singer shared a photo from the gala with the host himself. "Great job Leo," she captioned a snapshot of the two of them together on the red carpet.
Carey wasn't the only big name at the event. The "Wolf of Wall Street" star was also surrounded by close pals and former costars, Jonah Hill, Tobey Maguire and Edward Norton.
This is the 3rd consecutive year the Oscar-winning actor has held the gala to support research on climate change and bring environmental awareness.
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