JUST ADDED: 5 Seconds of Summer will be rocking the stage at this year's iHeartRadio Music Festival Village in Las Vegas! The band sat down with Ryan Seacrest to break the news. Click here to buy your tickets now, before they sell out!
The Lonely Island was the musical guest on "Late Night with Jimmy Fallon" Thursday night, where the comedic trio performed their song "YOLO" from The Wack Album.
Jimmy Fallon and The Roots were on hand to participate, natch, and what ensued was pure awesomeness!
Check it out: