Foo Fighters rocker Dave Grohl has formed a mystery supergroup which will make its debut at the Sundance Film Festival in Utah later this month (Jan13).

The star, who ended an amazing 2012 by performing with Sir Paul MCCartney at 12-12-12: The Concert for Sandy Relief, will take his bow as a filmmaker at the festival and he's planning to add a little star power to the launch of his documentary Sound City.

Grohl has announced his Sound City Players will perform in Park City on 18 January (13), insisting the band will feature "core musicians and special guests" from the film about the Los Angeles recording studio Sound City, where the rocker's former band Nirvana recorded their groundbreaking Nevermind album.