Jimmy Fallon Just Crashed a Jonas Brothers Concert to Perform "Mr. Brightside"

The Jonas Brothers have officially kicked off The Tour—and Jimmy Fallon just made an appearance as their surprise guest, serenading the massive crowd on their second night at Yankee Stadium in New York City.

Fallon's song selection? The Tonight Show Starring Jimmy Fallon Host left it up to the Jonas Brothers to deliver the tracks their fans love (the career-spanning tour is billed as "five albums, one night"). Instead, Fallon sang early 00's classic "Mr. Brightside" by The Killers while wearing sunglasses, and thousands of Jo-Bros fans enthusiastically joined him.

"Huge thanks to the Jonas Brothers for giving me the surprise guest spot on 'The Tour' tour," Fallon wrote on X after the August 13 show. "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." 

Nick Jonas's wife, actress Priyanka Chopra Jonas, was among those in attendance.

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Fallon also shared a hilarious video he made with the Jonas Brothers backstage, their joint contribution to the sound-effect-riddled "Dude, Did You Bring the..." TikTok meme. A+ facial expressions all around, guys. 

About "Mr. Brightside" 

First released in 2003, "Mr. Brightside" is The Killers' lead single from their 2004 debut album Hot Fuss. Cowritten by vocalist Brandon Flowers and band member Dave Keuning, "Mr. Brightside" remains their highest-charting hit, peaking at No. 10 on the Billboard Hot 100. 

Fallon was sure to thank the band after the Jonas Brothers concert as well, writing on X, "And thank you to The Killers for writing A JAM."

Joe Jonas, Kevin Jonas, and Nick Jonas of musical group Jonas Brothers during an interview with host Jimmy Fallon on Friday, April 7, 2023 Photo: Getty Images

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"Mr. Brightside" lyrics

Coming out of my cage
And I've been doing just fine
Gotta gotta be down
Because I want it all
It started out with a kiss
How did it end up like this?
It was only a kiss, it was only a kiss
Now I'm falling asleep
And she's calling a cab
While he's having a smoke
And she's taking a drag
Now they're going to bed
And my stomach is sick
And it's all in my head
But she's touching his chest now
He takes off her dress now
Let me go
And I just can't look, it's killing me
And taking control

Jealousy, turning saints into the sea
Swimming through sick lullabies
Choking on your alibis
But it's just the price I pay
Destiny is calling me
Open up my eager eyes
'Cause I'm Mr. Brightside

I'm coming out of my cage
And I've been doing just fine
Gotta gotta be down
Because I want it all
It started out with a kiss
How did it end up like this?
(It was only a kiss), it was only a kiss
Now I'm falling asleep
And she's calling a cab
While he's having a smoke
And she's taking a drag
Now they're going to bed
And my stomach is sick
And it's all in my head
But she's touching his chest now
He takes off her dress now
Let me go
'Cause I just can't look, it's killing me
And taking control

Jealousy, turning saints into the sea
Swimming through sick lullabies
Choking on your alibi
But it's just the price I pay
Destiny is calling me
Open up my eager eyes
'Cause I'm Mr. Brightside

I never
I never
I never
I never