The legendary band rocked out underground.
New York City is full of surprises! For example, when you realize those street performers on the subway are actually U2.
Bono, rocking a blue cowboy hat, and the whole band appeared, unannounced, at a subway stop underneath Grand Central Terminal where they played "Angel of Harlem."
The impromptu performance drew a throng of fans and sightseers who documented the unprecedented mini-concert on their phones and posted pics and clips on social media.
But the band wasn't alone. Joining them -- and dressed in some super casual street performer clothes -- was Tonight Show host Jimmy Fallon.
U2 is taking over Jimmy's show on Friday -- as they will be the night's only booking -- and it looks like this magic metro moment is likely part of a pre-taped segment for the band's special episode.
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U2 was originally supposed to appear for a special episode of The Tonight Show in November, but Bono's devastating bike accident -- which required extensive medical treatment and surgery -- postponed those plans.
It should be interesting to see what Jimmy and the guys have planned for the momentous episode.
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After Bono's painful accident in November, he was unable to perform with the band for several months. At a concert for World AIDS Day in New York, Chris Martin and Bruce Springsteen filled in for Bono, calling themselves "U2 Minus 1."
Check out the video below for a look at Martin and Springsteen singing some of the group's most iconic singles.
