Star Sightings: Katy Perry Parties After the VMAs, Leonardo DiCaprio and Orlando Bloom Head to Vegas & More!

Jeremy Scott and Katy Perry
Donato Sardella/Getty Images for UGG

See how A-listers are living it up during the dog days of summer.

After the awards show comes the after-party!

Following her hosting duties at the 2017 MTV Video Music Awards, Katy Perry rocked a leggy strapless Robert Cavalli Couture dress embroidered with a sequined bird to party with her designer pal, Jeremy Scott, at his collaboration launch event with UGG at Poppy in West Hollywood, California, on Aug. 27.

Jared Leto, Caroline D’Amore, Paris Jackson, Jasmine Sanders, Lil Yachty and G-Eazy were among those who joined the dynamic duo.

Donato Sardella/Getty Images for UGG

And there was plenty more party-hopping to be had!

Mel B stopped by Beauty & Essex Los Angeles’ Pawn Shop to nab a rose gold butterfly pendant before joining her America’s Got Talent co-star, Heidi Klum, for dinner. Hailee Steinfeld and Millie Bobby Brown also dined at the restaurant, munching on a truffle mac and cheese, kale and apple salad, tomato panzanella and the Mexican street corn ravioli. After dinner, all four, as well as Vanessa Hudgens, hit up the Republic Records After-Party at TAO Los Angeles, while The Chainsmokers, who also had a meal at Beauty & Essex, left for The Highlight Room for Calvin Harris’ post-VMAs soiree.

Poppy was also the place to be on Aug. 24, where Kendall Jenner, Kourtney Kardashian and her boyfriend, Younes Bendjima, Hailey Baldwin, Corey Gamble, Fifth Harmony’s Normani Kordei, Madison Beer, Blake Griffin, Jordan Clarkson and Justine Skye all stepped out at the new h.wood Group hot spot. “Kourtney and her boyfriend were canoodling all night long,” an eyewitness told ET. “They were hugging, kissing and dancing. They never left each other’s side. They seem super happy together!”

The other major event of the weekend was the big Floyd Mayweather vs. Conor McGregor fight in Las Vegas, which Mayweather won in a close 10-round battle.

Emily Ratajkowski didn’t have to worry about driving to the match, opting to take a Lyft instead.

Later that night, Orlando Bloom joined Wynn Resorts Chairman and CEO Steve Wynn and McGregor at Andrea's Restaurant in Encore at the Wynn Las Vegas. They hung out just ahead of the boxer’s Wynn Nightlife residency debut at the adjacent Encore Beach Club at Night.

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Jamie Foxx hosted a special fight night party at JEWEL Nightclub inside the ARIA Resort & Casino, which Leonardo DiCaprio and Tobey Maguire hit up at 2:30 a.m. with about 25 people. DiCaprio was dressed casually and had a black baseball cap pulled over his eyes, but sources tell ET he was amused when fans started chanting his name after Foxx announced that there was a "wolf" in the building.

Brody Jenner was also in Sin City, celebrating his 34th birthday with a DJ set at LIQUID Pool Lounge at ARIA Resort & Casino on Aug. 25.

Brandon Pearson

Once the fight and VMAs were over, it was time to focus on tennis! Luke Bryan took in courtside views of the U.S. Open opening night ceremonies from the Emirates Suite on Aug. 28.

Guy Martin/TLA Worldwide

Former hockey pro Sean Avery and his wife, model Hilary Rhoda, rocked the ping-pong table at the ASICS Open party on New York City’s Mulberry Street on Aug. 25. The soiree, which included immersive art installations, an oversized ball pit and specialty cocktails from Deep Eddy Vodka, Sailor Jerry Rum and Casa Noble Tequila, celebrated the kick-off to U.S. Open week.

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Venus Williams joined chef Jonathan Waxman for a cooking demonstration at Citi Taste of Tennis at W New York on Aug. 24.

Bennett Raglin/Getty Images for AYS World

Back in Los Angeles, pals Sarah Ramos and Alia Shawkat enjoyed a Cinespia screening of Ghost World at the Hollywood Forever Cemetery on Aug. 26. They were joined by comedians John Early and Kate Berlant, and other celebs who enjoyed a surprise appearance by the movie’s stars, Thora Birch and Illeana Douglas, as well as Matt McGorry, Alexa Chung and Rowan Blanchard.

Kelly Lee Barrett for Cinespia

Following the Los Angeles premiere of their new movie, The Layover, William H. Macy and Alexandra Daddario bonded at the SVEDKA Vodka-presented after-party at The Highlight Room on Aug. 24.

Amy Graves/Getty Images

Timbaland, Emma Bunton and Nick Carter celebrated the season finale of their competition show, Boy Band, at the Doheny Room in L.A. on Aug. 24, getting especially giddy when they heard “Eyes Closed” playing over the speakers. The song is by In Real Life, the band created on the show.

SBE

Also celebrating in the City of Angels was Rashida Jones, who launched her collaboration with celeb-fave luggage brand Away with an exclusive dinner at the Chateau Marmont in L.A. on Aug. 22. She was joined by pal Maya Rudolph, as well as Brad Goreski, Mark Ronson and Danielle Hai.

BFA

Some celebs even got their sweat on! Shay Mitchell worked out alongside fellow fitness fanatics at the Propel Co:Labs Fitness Festival in L.A. on Aug. 12.

Michael Simon

Over in the Big Apple, Krysten Ritter stepped out for the 10th birthday of 10022-Shoe at Saks Fifth Avenue New York on Aug. 17.

Samantha Mussman

After her concert at NYC’s Madison Square Garden on Aug. 19, Mariah Carey and boyfriend Bryan Tanaka were joined by their famous friends, including Adrien Brody and Kate Beckinsale, for a post-show dinner at Philippe. Her group of 30 dined in the Warrior 1 room, where they drank bottles of Dom Perignon Rose and indulged in chicken satay and Beijing chicken.

Gloria Estefan had a similar idea just hours after the final curtain came down on her autobiographical show, On Your Feet, sitting with a large group in the main dining room of Japanese restaurant Zuma New York on Aug. 27.

Nearby, Lili Reinhart had some fun at the St. Ives Mixing Bar in New York City on Aug. 14, creating her own custom face scrub with natural ingredients.

Michael Simon

Olivia Culpo also indulged in beauty products, picking up Jergens Wet Skin Moisturizer during a shopping trip.

Michael Simon

Ireland Baldwin got her hair whipped into shape by George Papanikolas at the Biolage R.A.W. flagship salon using the hair brand’s new styling collection. “I wanted to recreate the natural beach waves Ireland loves after being in the ocean,” the celebrity stylist explained. “We embodied her surfer girl personality and natural vibe with simple, textured waves, keeping the hair looking soft and beautiful."

Michael Simon

Victoria Justice was also spotted getting her glamour on. The Victorious alum and her sister, Madison Reed, did a fashion shoot with photographer John Russo at the Mondrian Los Angeles on Aug. 24.

Meanwhile, The Kitchen co-host Katie Lee hosted an Aperol Spritz dinner party at her home in The Hamptons over the weekend.

Sara Luckey

Nina Agdal got to work in NYC, helping preview tech entrepreneur Tarik Sansal’s new app, Romio, which debuts this fall.

Michael Simon

Nelly headed south to Mexico to kick off Farouk Systems' three-day conference with a performance at Moon Palace Cancun on Aug. 25.

Chefs Adam Kenworthy and Mikaela Ruben got goofy during a break from creating new recipes in New York City.

Not everyone hit the town, however! Rumer Willis had a mini staycation, getting cozy on her own personalized, custom-made Helix mattress on Aug. 19.

Click through the gallery below to see how else A-listers are living it big this month!