One time, Dave Grohl was at a party with Sir Paul McCartney, Taylor Swift and God only knows who else. McCartney hopped on a piano and started playing a new song—that’s crazy in itself, right? Afterwards, everyone wanted Grohl to play something. Admittedly, he was “super high” and didn’t know how to play piano. 

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Then, he looked around and saw that all of McCarney’s guitars were left handed. It was a bad situation getting worse, but then, to Grohl’s relief, Taylor Swift chimed in and offered to play a song. She got on the piano, started playing and then Grohl picked up a left-handed bass and attempted to play along—he didn’t initially realize that Swift was covering Foo Fighters’ “Best Of You.”

Grohl told this story in hilarious fashion during his acoustic performance at Cannes Lions 2016 Wednesday night. You can watch video of it below.