Surprise, surprise.

Leonardo DiCaprio's 2nd Annual Saint-Tropez Gala benefitting his foundation -- which works to protect the environment -- was filled with beautiful models and actresses alike on Wednesday night, including his reported girlfriend, 24-year-old Sports Illustrated model Kelly Rohrbach. Rohrbach and 40-year-old DiCaprio have made no secret of their summer romance, snapped smooching during a bike ride in New York City last month.

Check out Kelly flashing her enviable abs in a cut-out purple gown next to model Jessica Stam, who flashed her black underwear in a super-sheer Francesco Scognamiglio creation.

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But this being a DiCaprio party, Rohrbach, of course, wasn't the only gorgeous woman in the room showing off her enviable physique. Kate Hudson looked amazing as usual in a low-cut Julien Macdonald dress, posing next to former Vampire Diaries star Nina Dobrev in an elegant white Reem Acra gown.

Fast & Furious star Michelle Rodriguez is no stranger to the overseas party circuit, and showed a whole lot of skin in this sheer gown almost rivaling Jessica Stam's.

Not to be outdone, supermodel Naomi Campbell proved she's still got it at 45 years old, rocking a lingerie-like, super-sexy black gown featuring a thigh-baring slit.

Chrissy Teigen also made an appearance with her husband, John Legend, but covered up in a printed yellow-and-black creation.

The Wolf of Wall Street actor was supported by his famous pals Wednesday night, including Elton John, Sylvester Stallone, Chris Tucker, Adrien Brody, Marion Cotillard, Goldie Hawn, Heidi Klum, and Orlando Bloom. The Oscar-nominated actor slicked back his hair for the occasion, rocking a substantial beard.

But it wasn't all partying in St. Tropez. The gala's live auction raised over $40 million for the Leonardo DiCaprio Foundation, which will go towards protecting Earth’s last wild places and implementing solutions to preserve and save the environment.

"We've decimated our forests, wildlands, polluted and over fished our rivers and oceans; all the key ecosystems that not only serve as a home to our planet’s biodiversity, but also make life here for us possible," DiCaprio said in his opening speech. "I'm incredibly proud to be part of a night that will allow us to do so much to protect the planet."

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In May, DiCaprio was rumored to be romancing none other than Rihanna.  Watch the video below for more on their rumored superstar coupling:

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