The duo symbolically got up on the Grammy stage without their pants on after Josh Dun said if they'd ever make it there, they'd get on stage pantless.
"Anyone from anywhere can do anything," Tyler Joseph said while accepting the award.
Tyler Joseph and Josh Dun are nominated for five Grammys at this year's ceremony, including Record Of The Year, Best Pop Duo/Group Performance, Best Rock Performance, Best Rock Song and Best Song Written For Visual Media.
AP 342 cover stars Twenty One Pilots released their double-platninum, fourth album, Blurryface, in May 2015. It has sold well over one million copies in the U.S. alone, producing the top 10 singles "Stressed Out" and "Ride."
Check Twenty One Pilots on the Emotional Roadshow tour right now.
Why did Twenty One Pilots take off their pants? They turned back time, to the good old days
By the time Tyler Joseph and Josh Dun of Twenty One Pilots accepted their pop duo/group performance Grammy for "Stressed Out," they were no longer wearing pants.
Turns out they had a pact where they would turn back time, to the good old days, before they were making money playing music.
Joseph explained: Back in the day, he and Dun and some other guys got together to watch the Grammys, and somewhere along the line they noticed that they were all in their underwear.
"And seriously," Joseph said, "Josh turned to me -- and we were no one at that time -- and he said, 'If we ever go to the Grammys, if we ever win a Grammy, we should receive it just like this."
James Corden followed it up by stripping down to his underwear to introduce Ed Sheeran.
Twenty One Pilots Goes Pantsless to Accept the Award for Best Pop Duo/Group Performance at the 2017 Grammys
There really is no dress code at the 2017 Grammys. Just ask Twenty One Pilots.
After winning the award for Best Pop Duo/Group Performance for their hit song "Stressed Out," Twenty One Pilots members Tyler Joseph and Josh Dun immediately got up and removed their pants, choosing to walk up to the podium in their underwear. (Briefs > boxers, for this duo, BTW.) Yes, they really did drop trou on music's biggest night. But before you think it was a stunt, Tyler used the duo's acceptance speech to explain the OMG moment.
"This story, it starts in Columbus, Ohio, it was a few years ago and it was before Josh and I were able to make money playing music," he explained. "I called him up, and I said, 'Hey Josh, want to come over to my rental house and watch the Grammys? As we were watching, we noticed every single one of us was in our underwear, and seriously, Josh said to me, and we were no one at the time, he turned to me and he said, 'If we ever go to the Grammys, if we ever win a Grammy, we should receive it just like this.'"
His speech earned laughs and applause from many members of the audience, including Rihanna and Halsey, who were also nominated in the category. (Even host James Corden later felt inspired to drop trou!)
He finished his speech with an inspirational message, saying, "I want everyone at home whose watching to know that you can be next. So watch out, OK, because anyone from anywhere can do anything."
And they can do it without wearing pants.
To take home the award, Twenty One Pilots beat out The Chainsmokers and Halsey's "Closer," Lukas Graham's "7 Years," Rihanna and Drake's "Work," and Sia and Sean Paul's "Cheap Thrills."