Christina Aguilera and Jimmy Fallon surprise unsuspecting subway riders. On The Tonight Show, Christina Aguilera and Jimmy Fallon went in disguise and surprised unsuspecting subway riders with a free little concert.The two attempted to go incognito by covering themselves in hats, sunglasses, wigs, and unglamorous clothing, while performing Aretha Franklin’s “Think.” But, honestly, who were they kidding? While the costumes were pretty good, it’s impossible to hide one of the greatest