Jennifer Lawrence (top right) and Amy Schumer (bottom right) partied hard in the Hamptons this summer. (Photo: Instagram)

Jennifer Lawrence (top right) and Amy Schumer (bottom right) partied hard in the Hamptons this summer. (Photo: Instagram)

Jennifer Lawrence and Amy Schumer know how to liven up a Billy Joel concert. The piano man was joined on stage by the dynamic duo in Chicago last night. They put on quite a show, frolicking and dancing on the old’ man’s piano!

Joel, 66, was cool with the scene and kept right on singing his 1983 hit “Uptown Girl.”

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Lawrence and Schumer have become best buds since they met over the summer. They vacationed in the Hamptons. Now they’re writing a comedy movie together.

Joel has a connection to Shumer as well. His song, “Uptown Girl,” is part of the soundtrack to Schumer’s movie “Trainwreck.” So it only seemed natural that Lawrence and Schumer would crash the stage.

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But they didn’t stop there. They actually kicked off their shoes and climbed up on Joel’s piano. They danced like no one was watching after Lawrence paused to nibble on Schumer’s toes. WTF?

Kyle Dunnigan, a writer on Schumer’s Comedy Central show, “Inside Amy Schumer” captured the scene on video and posted it on his Instagram account.

It wasn’t all spontaneous, of course. Lawrence and Schumer rehearsed their appearance with Joel before the show.

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“Rehearsals a little rough,” Dunnigan wrote in one caption.

“Get ready for a bunch of billy joel photos. Me amy schumer and jennifer lawrence are going on stage tonight.”

Schumer’s sister, Kim Caramele, also was busy with a camera. She film the group dancing in a chorus line. “Thursday’s with @caramelodies @amyschumer @kyledunnigan1 Oh and jlaw,” she wrote.

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Lawrence tipped her trip to Chicago in an interview Wednesday (Aug. 26) in The New York Times.

“I’m flying out tomorrow to see her in Chicago. We’ll write a little bit with her sister, Kim, who worked with Amy when she was writing Trainwreck,” she said about their comedy film.

Fortunately, it wasn’t all work and no play.

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Clearly I have the best moves

A video posted by @caramelodies on