Billie Eilish - our resident 'Bad Guy' - has a signature look, so it's always pretty easy to spot her in a crowd.
However, wanting to surprise a bunch of her fans, Billie disguised herself on the Ellen show, and her fans reactions are amazing!
WATCH Billie Eilish goes undercover on The Ellen DeGeneres show and surprises her fans:
A bunch of fans got together while a producer from the show asks them what they love most about Billie.
Little do they know that she is standing right there with them.
Some responses warm Billie's heart, with her fans expressing how much how music has impacted their lives for the better.
Eventually, the producer asks the girls if they would like to tell this to Billie's face, which they all obviously squeal 'YES!'
It then hits them that she has been there the whole time.
"Do you see my outfit?!" asks Billie when she rips off her wig. "Have you seen me wear pants like this?"
What an amazing prank!
WATCH Dove Cameron sings Billie Eilish's song "Bad Guy":
What a star.
WATCH Dove Cameron sings Billie Eilish's song "Bad Guy":
