What Does the Fox Say? Ylvis Performs Live with Jimmy Fallon and The Roots

I know it'll be stuck in your head all day, but there was no way I couldn't post Ylvis performing The Fox on last night's episode of Late Night. The Norwegian duo of Bard Ylvisaker and Vegard Ylvisaker made their late-night debut and were joined by Jimmy Fallon and The Roots.

According to the YouTube comments accompanying this clip, Ylvis actually performed the song twice, allowing the show to cut a version that switched back and forth between costumes and no costumes.

Now we all know what the fox says.