Jimmy Fallon surprised fans as he performed a song at a recent Jonas Brothers concert.
The Tonight Show host shocked concertgoers by taking to the stage at the New York City concert on Sunday and performing The Killers' 2003 classic hit Mr. Brightside.
Fans who attended the sold-out show at Yankee Stadium captured the surprise performance and shared the clips on social media.
"I asked the (Jonas) brothers, they said yes, but how would you all like to be in the world's biggest karaoke party for two minutes?" Jimmy, 48, asked the crowd, according to a video posted by a fan.
"I hope you know the words, this is Mr. Brightside," he added, before encouraging the crowd to join in while dancing energetically.
Another video shows Jimmy telling the audience, "I've brought my boombox," gesturing to a portable speaker that he was wearing as a cross body bag.
"Huge thanks to the Jonas Brothers for giving me the surprise guest spot on The Tour tour," Jimmy wrote on Twitter/X after the gig. "And thank you to Yankee Stadium for turning it into the world's biggest karaoke party. This is one of those nights I will never forget."
Jimmy added in a separate post, "And thank you to The Killers for writing A JAM."
Since the show, fans have flooded to social media to comment on the performance.
One fan commented on TikTok, "I would pay to go to a karaoke concert with jimmy fallon as the headliner."
Another TikTok user wrote, "He's been waiting on this moment and he deserves it."
The band, comprised of Kevin, Joe and Nick, are currently performing across the U.S. as part of their nationwide tour, titled The Tour. Their final U.S. show will take place on 9 December in Brooklyn, New York. The brothers will then begin the next leg of the trek in New Zealand, Australia and Europe.