VIDEO : Paul McCartney, Scarlett Johansson, and the Roots Sing Wonderful Christmastime

A member of the Avengers is getting into the Christmas Spirit with The Tonight Show host Jimmy Fallon, his legendary band The Roots, and musical icon Paul McCartney. Black Widow actress Scarlett Johansson, who was confirmed for Avengers: Infinity War earlier today, joined the impressive line up to perform "Wonderful Christmas" on NBC's Tonight Show this week. Also joining to sing were Matthew McConaughey, Reese Witherspoon, Tori Kelly, and Seth McFarlane in the a cappelle rendition.