Ever since Jimmy Fallon and Mariah Carey played her classic Christmas hit "All I Want For Christmas Is You" on classroom instruments, it's been hard for the late-night host to even top himself with any other sing-alongs -- that is, until 2016.
In one of his Brady Bunch-style performances, Fallon recruited his Roots band along with the likes of Reese Witherspoon, Matthew McConaughey, Tori Kelly, Seth McFarlane and Scarlett Johansson to sing a harmonious version of Paul McCartney's "Wonderful Christmastime." And to really get into the holiday spirit, of course McCartney tagged along for the caroling bit.