Stop the presses!!
In all honesty though, we're a bit shocked!
Justin shared the photo on Sunday and captioned it:
[Image via Justin Timberlake/Instagram.]
We all know Keira Knightley can act and model - but who knew she could sing too??
If the song sounds familiar, it's because Adam Levine played a version of it in an early clip of the film.
If Keira's voice sounds familiar, we think it's because she sounds a lot like Nina Persson from The Cardigans.
Ch-ch-check out the video (above) to see the lyric video/movie trailer/musical debut of Keira Knightley!