An undercover Miley Cyrus performs in New York City subway—and promptly turns station into a dance party.

Pop star Miley Cyrus and Jimmy Fallon, host of The Tonight Show, went busking undercover Wednesday night in a New York subway station and turned the platform into a dance party.

At first, Cyrus was almost unrecognisable in a long black wig, cowboy hat and dark glasses. (Fallon wore a similar disguise and called himself “Bart” for the performance.)

But the moment Cyrus and Fallon opened with their cover of Dolly Parton’s Jolene, riders quickly to recognised the voice of the 24-year-old former Disney star.

As the crowd grew, Fallon took off his wig and glasses and introduced she-who-needs-no-introduction Cyrus.

Understandably, the lucky Wednesday night commuters went crazy with excitement.

As a finale, the duo performed an acoustic rendition of Cyrus' 2009 hit Party in the USA.

The crowd—now stretching in every direction—joined in dancing and singing, with Fallon passing the microphone through the audience.

The stunt was filmed by NBC's The Tonight Show Starring Jimmy Fallon and took place in the subway station just under the Rockefeller Center in New York.

Goosebumps.