The two surviving Beatles are back together!

Paul McCartney and Ringo Starr reunited at the world premiere of director Ron Howard's documentary, "Eight Days a Week," in London on Thursday night.

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The film examines the iconic group's meteoric rise and inexorable link to each other even after their breakup.

"For so long we were a foursome, then we split up, but we were still a foursome," McCartney said while discussing the film. "We were the ex-Beatles."

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"And then when John [Lennon] passed away, it was a very difficult for all of us," he added. "It was a loss that was felt by the world, so you can imagine how it hit us."

"If you like the Beatles, you're gonna love this," Starr said of the doc.

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