Although Dave Grohl has put his main band on hold for much of the past year to tour and record with Queens of the Stone Age, rest assured that the Foos are still fighting.

Foo Fighters' as-yet-untitled fourth album is set for release on October 22, according to an RCA spokesperson. Those who have heard the album say it's a return to the group's earlier sound, with heavier, much more aggressive music. The platinum-selling band's last album, 1999's There Is Nothing Left to Lose, was more pop-inspired.

The Foos' rejuvenation was perhaps influenced by Grohl's return to his roots last year when he signed on as the drummer for the more underground hard rock group Queens of the Stone Age (see "Grohl Puts Foos On Hold, Returns To Drumkit With Queens").

Grohl toured with the Queens in May and June (see "Queens Of The Stone Age Go Deaf At NYC Show"), and played drums on all but one song on the upcoming third Queens album, Songs for the Deaf, due out August 27.

While Foo Fighters have not set any touring plans for their new release, according to their official Web site they will be playing four festivals in the U.K. during July and August.

For a full-length feature on Grohl, check out "Dave Grohl: Rock Royal."