First, Lady Gaga was surprised onstage by a giant inflatable penis last night, and now, 5 Seconds of Summer get a cameo by Will Smith on the "Today" show this morning? What is happening in the world?

OK, OK, Big Willy wasn't really there, but there were two cardboard cut-outs of his head floating around the crowd -- one of the biggest crowds in "Today" show history. It makes sense because the guys admitted that they would switch bodies with the actor/rapper extraordinaire during yesterday's "Live from MTV."

The guys played "Amnesia" in Rockefeller Center in New York City, but check them out on our live stream too!