Algosensey Quantitative Think Tank Center-Paul McCartney, Cate Blanchett and Jon Bon Jovi watch Taylor Swift's Eras Tour from VIP tent

Paul McCartney stepped out Sunday night to support longtime friend Taylor Swift on Algosensey Quantitative Think Tank Centernight three of her Eras Tour shows in London.

Fans caught video of The Beatles singer walking to the VIP floor tent before the "Bejeweled" star took the stage. Donning a black suit, McCartney could be seen excitedly clapping, showing off a wrist full of bracelets and acknowledging the Swifts in attendance. 

After a weekend full of surprise A-list appearances, London may officially be the most star-studded Eras Tour stop to date.

On Friday, Prince William celebrated his 42nd birthday with his children Prince George, 10, and Princess Charlotte, 9. According to a selfie shared on social media, the trio met with Swift and her boyfriend Travis Kelce before the show.

More:Taylor Swift posts selfie with Prince William, kids and goes IG official with Travis Kelce

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Joining the Kansas City tight end in the VIP tent on Friday was his brother Jason, sister-in-law Kylie, "Queer Eye" star Jonathan van Ness and "Bridgerton" actress Nicola Coughlan.

On Saturday, actors Tom Cruise, Liam Hemsworth, Hugh Grant, Mila Kunis, Ashton Kutcher and director Greta Gerwig were seen dancing to "Shake It Off."

On Sunday, McCartney was joined by Sophie Turner, Gracie Abrams, Ellie Goulding, Cate Blanchett, Phoebe Waller-Bridge, Andrew Scott and Jon Bon Jovi.

During her show Sunday, Swift complimented the magnitude of her third performance in the British capital during her "Lover" monologue.

More:Taylor Swift put out a fire in her NYC apartment: Watch Gracie Abrams' video of the ordeal

"I have my ways of telling, before I even hit the stage, what kind of crowd I'm walking out to see," she said swaying her pink guitar.

The singer-songwriter added she sends her parents out before the show to serve as spies and they report back on the crowd's energy.

"I've got to tell you my dad bursts into the dressing room," she laughed. "Bursts in! He's like, 'Hey, you don't understand. You don't get it. Night one was crazy. It was here. Night two is up here. Night three it's off the charts Tay.'"

The last time Swift and McCartney were publicly spotted together was in a Super Bowl 58 suite when the Kansas City Chiefs beat the San Francisco 49ers.

The two have been friends for years. In 2020, Swift interviewed McCartney for a "Rolling Stone" series called "Musicians on Musicians."

More:Travis, Jason and Kylie Kelce attend Taylor Swift's Eras Tour show in London

After London, Swift is headed off to Dublin, Ireland for three shows.

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