Famous people surprising their fans is the late night gift that keeps on giving.
We've had Lizzo singing in people's ears, Tina Fey popping out to hug lovers of Mean Girls — and now it's the turn of Michelle Obama, who jumps out from behind the curtain of a bookstore in the Tonight Show clip above to say hello to fans browsing her new book display.
The common thread of all these videos? Jimmy Fallon hovering awkwardly in the background, not quite sure if he's part of the surprise or not.