When Lin-Manuel Miranda was starring on Broadway in the musical Hamilton, he began a bit of a tradition called "Ham4Ham," where he'd come outside the stage door and briefly entertain the looooong lines of the crowd waiting there. And often he'd bring out a guest celebrity.
On this particular day, he brought with him Lea Salonga to sing a duet of "A Whole New World," from the animated film Aladdin, for which she'd provided the singing voice of the Princess. The video is fun for a few reasons. One is that Miranda is clearly a big fan of the movie and and an even bigger fan of Lea Salonga and is pretty excited to be singing the song with the original Princess. And also, around 1:40 in, Salonga appears to throw an unexpected surprise his way. It's certainly possible he knew beforehand, but that doesn't appear to be the case.