Christina Aguileria and Jimmy Fallon went busking in disguise in New York Subway in disguise although it's kind of hard to not recgonise Christina's mind blowing voice.
As they covered Aretha Franklin's "Think," passersby on the 47-50 Street Rockefeller Center platform took notice of Aguilera's unmistakable vocals and filmed the surprise performance on their phones.
The duo then removed their not-so-glam disguises. "It's so it in here!" Aguilera said. "Oh, my God!" The jig was up, so Aguilera and Fallon gave the fans what they wanted, a performance of "Fighter!"
