Jimmy Fallon was the surprise guest at the Jonas Brothers Yankee Stadium concert Sunday night. Tonight Show host Jimmy Fallon made an unexpected appearance, joining the Jonas Brothers onstage and leading the crowd in a sing-along version of The Killers’ “Mr. Brightside.”

🎥: Peter Shapiro

Fallon tweeted:
"Huge thanks to @JonasBrothers for giving me the surprise guest spot on ‘The Tour’ tour. And thank you to @yankeestadium for turning it into the world’s biggest karaoke party. This is one of those nights I will never forget,”

Subscribe to The Relix Channel for more videos + livestreams: http://bit.ly/2zEruld