New besties Jennifer Lawrence and Amy Schumer danced on-stage with Billy Joel last night

Who knew Jennifer Lawrence and Amy Schumer were such besties?

It was only the other day when we found out the two were writing and co-starring in a movie together. Now, they're executing choreographed flash mobs with music Hall of Famers.

Hollywood's new dynamic duo appeared on-stage with Joel during his concert at Chicago's Wrigley Field on Thursday night. Schumer and Lawrence appeared with a group of folks, which included Schumer's sister Kim Caramele and Inside Amy Schumer writer Kyle Dunnigan, according to EW.

Before we get into the actual performance, take a look at the rehearsal:

Joel gave a hint at the beginning of his hit song, "Uptown Girl," when he asked, "Any of you guys seen the movie "Trainwreck"? 

Here's a couple shots of the duo climbing on to Joel's piano (Alert: In the first one, JLaw licked Schumer's feet.)

 

 

Those kids. Watch the good times below (starting at about 2 minutes in):