Amy & JLaw: Uptown Girls! – ARTICLE

Billy Joel has added two new "Uptown Girls" to his onstage roster – Jennifer Lawrence and Amy Schumer!

The actresses and new BFFs made a surprise cameo during the singer's performance of his classic song at a Chicago concert on Thursday.

Amy was the first guest to appear, kicking off a reenactment of the closing scene from her hit comedy "Trainwreck," before being joined by a group of friends, including JLaw. The two stars then turned the routine into a duet, removing their shoes and shimmying atop Billy's piano for the duration of the number.

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The comedienne shared a quick clip of the appearance on Twitter, and later thanked Billy for his hospitality.

"The very best," she wrote of the "Piano Man" crooner.

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Amy and Jennifer became fast friends after meeting in July, and have already planned much more than crashing concerts together.

As previously reported on AccessHollywood.com, Jen let slip during a recent New York Times interview that she and the "Inside Amy Schumer" star have been working on a screenplay.

"We’re almost done writing. It just flowed out of us," JLaw said of the project. "We’ve got about 100 pages right now."

The Oscar winner went on to reveal that she was inspired to contact Amy after seeing "Trainwreck," telling the paper she fired off a very succinct email.

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"I said, 'I don’t know where to get started. I guess I should just say it: I’m in love with you,'" the "Hunger Games" star admitted. "We started emailing, and then emailing turned to texting."

-- Erin Biglow

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