Paul McCartney, Jimmy Fallon, The Roots, and the Cast of ‘Sing’ Perform an A Cappella Rendition of ‘Wonderful Christmastime’

Jimmy Fallon and The Roots join Paul McCartney, Matthew McConaughey, Reese Witherspoon, Scarlett Johansson, Seth MacFarlane and Tori Kelly for an a cappella rendition of “Wonderful Christmastime.”