It's been a few months since Britney Spears released her ballad-filled eighth studio album.  Now, Britney is going unplugged on her latest rework of the somber single, "Passenger".  This time, Mama Spears gets a little help from song co-writer Sia.

Are you guys feeling the toned down version more than the original?

Listen, below, as the two superstars croon melodically over guitars played by Nick* & Country Club Martini Crew.

h/t: Idolator