Another big-name act has been added to the ever-growing talent roster at tonight's 12-12-12 Concert for Sandy Relief in New York City: Nirvana. And they'll be backing Sir Paul McCartney.

The Telegraph in London reports that Nirvana drummer Dave Grohl and bassist Krist Novoselic, along with unofficial fourth member Pat Smear, will back McCartney on a brand-new song.

It will be the first time the surviving members of the pioneering grunge band have played together in 20 years, with or without a former Beatle behind the mic.

Grohl, Novoselic and Smear worked on the track with McCartney in a studio session after McCartney said he called Grohl, 43, who asked him to come along to “jam with some mates."

The 12.12.12 Concert for Sandy Relief, which takes place at Madison Square Garden tonight, will feature Eric Clapton, The Rolling Stones, Eddie Vedder, Roger Waters, The Who, Chris Martin, Bruce Springsteen, McCartney, Grohl and Bon Jovi, to name just a few. Proceeds from the event will aid the Robin Hood Relief Fund.

The concert will be televised and streamed tonight; check local listings for participating TV channels, and head here for a list of websites that will be streaming the event.

For more information about the concert, and to donate, visit 121212concert.org