The Foo Fighters started their weeklong 'Late Show With David Letterman' residency in style last night, calling on country star Zac Brown to help them run through a raging rendition of Black Sabbath's classic 'War Pigs.'

As previously reported, the band plans to spend the week performing covers that tie in somehow with the material it wrote and recorded for its new 'Sonic Highways' album. 'War Pigs' seems like a slightly curious choice, given that the group has talked up the record as a sort of love letter to American music, but when the results are this righteously ragged, we're inclined to give everyone involved the benefit of the doubt.

This is a big week for the band; they're set to debut the first 'Sonic Highways' single, 'Something From Nothing,' on Oct. 16, and the eight-part HBO series they filmed in conjunction with the album will air its first installment the following day.

Along the way, we can expect a few more nights of the Foos flying their rock 'n' roll flag on 'Letterman' -- check out their 'War Pigs' performance above, and watch frontman Dave Grohl's interview segment from last night's episode below.

Dave Grohl on 'Late Show With David Letterman'