Taylor Kinney and Lady Gaga attend the Weinstein Company's pre-Oscar dinner. Credit: Stefanie Keenan/Getty Images for Chopard

Some of the biggest names in Hollywood joined together in celebration before Sunday night’s 88th Academy Awards. Stars including Lady Gaga, Justin Timberlake, Jessica Biel, Brie Larson and Michael Keaton hung out and socialized at several star-studded events.

It was a couples' night at the Weinstein pre-Oscars dinner at the Montage Marchesa Ballroom in Beverly Hills on Saturday, February 27. According to a source, pregnant Chrissy Teigen was spotted bringing John Legend into the ladies room to help unzip her dress, as he joked, “Gotta practice for the baby!”

Lady Gaga and her fiancé, Taylor Kinney, also attended the Heineken-sponsored event, showing up toward the end of the night. The couple posed for some photos before chatting with Lana Del Rey, who excitedly hugged the “Born This Way” singer.

A photo posted by Lady Gaga (@ladygaga) on

Newly engaged pair Maks Chmerkovskiy and Peta Murgatroyd were also at the event where their Dancing With the Stars costar Derek Hough performed two numbers from his upcoming Broadway show, Singing in the Rain.

Matt Damon and his wife, Luciana, attended the William Morris Endeavor pre-Oscars party on Friday, February 26. According to a source, they were “beyond adorable” as they hit the dance floor together at the event.

Justin Timberlake and Jessica Biel were also in attendance at the WME party. The parents of Silas, 10 months, even carried out a small pizza from Jon & Vinny’s, who catered the event.

Brie Larson, Eddie Redmayne, Pharrell Williams, Kristen Stewart and more were seen at the Chanel pre-Oscars dinner at the West Hollywood restaurant Madeo. Larson, 26, who is nominated for an Academy Award for best actress for her role in Room, briefly spoke with Redmayne, 34, and his wife, Hannah Bagshawe.

Michael Keaton and his mystery date enjoyed themselves at the Michael Sugar and Grey Goose pre-Oscars party at the Sunset Tower Terrace in West Hollywood on Saturday, February 27. They held hands as the actor led her through the crowd, which included stars such as Mark Ruffalo, Emma Stone, Kate Upton and Chace Crawford.

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