Tons of other A-listers partied at Wynn Las Vegas as well, including a very sexily dressed Kate Hudson.
After recently reuniting at Coachella, Rihanna and Leonardo DiCaprio were spotted together once again, this time at Intrigue Nightclub's grand opening at Wynn Las Vegas.
The 27-year-old pop star was already in Vegas this weekend for her ANTI World Tour, which stops at Mandalay Bay on Saturday night, and an eyewitness told ET that she decided to make a surprise appearance at Friday's star-studded bash during the wee hours of the morning.
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Upon her arrival at 3:25 a.m., Rihanna made her way through a frenzied crowd and into the VIP area of the nightclub, where she was eventually seen chatting with DiCaprio. The eyewitness revealed that the two were "whispering into each other's ears."
RiRi sported a black trench coat with "Hellboy" written on the back and kept her hair slicked back in a tight ponytail, while DiCaprio dropped by in a a long-sleeve shirt and sweater, jeans and a grey newsboy cap.
Later that night, The Revenant actor ducked out with a buddy and a large group of other clubgoers just as Rihanna left with her entourage. "She walked behind Leo and not close to him," the source told ET. DiCaprio eventually ended up at Wynn Tower Suites, along with Rihanna and One Direction's Louis Tomlinson, who was also seen at the grand opening.
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The lavish bash was a total who's who of Hollywood, with a guest list that also included Kate Hudson, Vanessa Hudgens, Olivia Culpo, Charlotte McKinney, Ne-Yo, Karrueche Tran, Lauren Conrad and Michael B. Jordan.
Hudson was a beaming beauty in a black MILLY jumpsuit that featured an ultra low-plunge, which she paired with Brian Atwood black open-toe pumps and a Jimmy Choo clutch.
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After dining at Wynn restaurant SW Steakhouse, Hudson sipped on a vodka cocktail at Intrigue, where the 37-year-old actress got her very own Belvedere bottle. Check out the pic of her personalized souvenir from the party, which Hudson posted to her Snapchat.
Hudson turned the grand opening celebration into a "girls night," partying in Sin City with a few of her gorgeous pals.
The Mother's Day star also posted a photo of herself letting loose in her hotel room before the event, wearing just a fringe bikini, sunglasses and a Las Vegas baseball cap. "What happens in Vegas stays in Vegas....or...ends up on Instagram to 4.1 million people," she captioned the snap.
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When Hudson isn't letting her hair down in Sin City, she's setting the record straight on that dinner date with NFL pro J.J. Watt. Let her explain in the video below.
