Fans at Paul McCartney’s Vancouver concert last night received a special treat when Sir Paul was joined onstage by a special surprise guest.

“We’ve got a young man here who’s a friend of mine,” McCartney told the audience. “I think you just might know him. He’s off The Tonight Show — Jimmy Fallon!”

Fallon hopped onstage sporting a New York Yankees cap, which he quickly swapped for a Canucks cap instead, and wished the weed-friendly city a happy 4/20, reports VanCity Buzz.

Related:Paul McCartney’s Legacy Beyond The Beatles

The former Beatle and the Tonight Show host proceeded to rip the roof off Vancouver’s Rogers Arena with a blistering duet of the Fab Four’s “I Saw Her Standing There,”; with the momentous occasion captured by numerous fans in attendance and shared via on social media.

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Unexpected guest last night #paulmccartney #jimmyfallon #RogersArena

A video posted by Ryan Planinshek (@rplaninshek) on Apr 21, 2016 at 6:13am PDT

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#paulmccartney #jimmyfallon

A video posted by Ryan (@grandpa_green) on Apr 21, 2016 at 12:56am PDT

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