Will Paul McCartney's jam session with the former members of Nirvana possibly make up a new super group? 

The 12 12 12 Concert for Sandy Relief was most definitely a star studded event and there were some pairings that you could see coming a mile away. Then there were others that were head scratchers. Like the Paul McCartney and Nirvana mash up. Where did that come from? Well, it turns out that Paul McCartney himself didn't see it coming either. In fact, he didn't even really know who Nirvana was before they teamed up.

According to the UK Guardian, the former Beatle wasn't exactly sure who he was being asked to jam with when someone told them "they" were Dave Grohl, Pat Smear and Krist Novoselic and were all members of the groundbreaking Seattle based grunge group Nirvana. So, he took a "crash course" on the group to get a better handle on their music. Paul eluded to this fact before they played on Wednesday night and was told that he would be playing the role of the late Kurt Cobain.

So, how did all of this happen? Turns out, it was Dave Grohl's idea and he suggested that they all get together to play before the show. The trio hadn't performed since Kurt died of a self inflicted gunshot wound in 1994. This turned out to be a very wise idea because out of this jam session came the song Cut Me Some Slack, which made its world premiere at the concert.

If you like the song, it's the title track for new documentary called Sound City that's directed by Dave Grohl. He got the idea for the film because that's where his former band recorded their breakthrough album, Nevermind. The studio was selling some items that Dave bought, including the mixing board when the studio closed last year.

The film is set to make its debut at the Sundance Film Festival in January.

Check out the trailer!