Plus, watch other A-Listers dance to Adele's tunes in the crowd!
From the words of Adele, "Send my love to your new lover."
Rumored couple Katy Perry and Orlando Bloom attended the singer's sold-out concert at The Wiltern in Los Angeles on Friday, where Perry's ex, John Mayer, wasn't too far away -- with a mystery brunette.
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Looks like Mayer's new girl has a broad taste in music -- just check out that Tupac shirt!
The exes didn't cross paths, however, as a source tells ET that Perry entered through the front of the venue, while Mayer made his way into the show through a back entrance. Mayer and the new girl didn't hold hands or show any PDA either, and at times it looked like they were trying to avoid being photographed together.
Inside the theater, Adele performed hits from her latest record-breaking album, 25, for approximately 1,000 people, including other A-listers like Jennifer Lawrence, Emma Stone, Woody Harrelson, Sam Smith, Josh Groban, Robbie Williams, Tom Hanks and Rita Wilson. Williams, a British pop singer, is a good friend of Adele's, and the pair even went on a double date the night before.
According to another eyewitness, "Everyone was dancing, having a good time and singing along to every song."
Clearly, they were having a blast.
WATCH: Katy Perry and Orlando Bloom Continue to Spark Romance Rumors
A source tells ET that Adele kept the set simple. She had no backdrops or special lights, explaining on stage that she's saving those "surprises" for her tour, which kicks off Feb. 29 in Belfast, Northern Ireland.
The 27-year-old singer was all about making fans happy at the intimate concert. According to a source, tickets sold for $50 or less, a request made by Adele herself. Throughout the entirety of the show, Adele couldn't help herself from taking selfies and having personal chats with audience members. At one point, she even ran off stage to find a recording device in order to video tape the crowd singing "Hello." She also had them sing Happy Birthday to a fan named Marissa, who was celebrating her special day with friends.
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Another highlight was when the diva took the stage to perform "I Miss You" for the very first time. She also sang "When We Were Young," "Water Under the Bridge" and "Million Years Ago," off 25.
Adele, of course, couldn't end the night without belting out some her classics, like "Rolling in the Deep," "Rumor Has It," "Set Fire to the Rain" and "Turning Tables."
After the show, Adele said hello to her fans outside of the venue, adorably peaking her head out of a window. She waved and snapped pics of them on her phone, then asked for a moment of silence, with a giddy "Shh!" gesture included. A source tells ET that she said, "I feel like Justin Bieber" after the concert.
Following the show, the celebrities who attended couldn't help but gush over the British singer's talent.
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"Adele. What a show. What a voice. What a woman. What an artist. What a date! Thank you. Hanx." Hanks shared on Facebook.
Adele. What a show. What a voice. What a woman. What an artist. What a date! Thank you. Hanx.http://www.whosay.com/l/TzLbuOP
Posted by Tom Hanks on Friday, February 12, 2016
Groban was just as impressed.
Mayer didn't post any videos from the actual show, but he did share a Snapchat of himself playing his own version of "Hello" on the piano, or as he called it, "Yello."
WATCH: Adele Photobombs Her Fans!
Adele is gearing up for her highly anticipated performance at the 58th Annual GRAMMY Awards, airing Monday on CBS at 8 p.m. ET/5 p.m. PT.
As we patiently wait for her to steal that show, watch the video below to see her adorably photobomb fans as part of her Adele: Live in London special.