Foo Fighters will be the retiring David Letterman's final musical guests tonight, putting a capstone on a lengthy period of mutual admiration.

Letterman -- on his first show back after undergoing open-heart surgery on Feb. 21, 2000 -- memorably introduced a Foo Fighters rendition of "Everlong" as “my favorite band playing my favorite song,” Dave Grohl and company, who have been frequent guests on the program over the years, also took part in the Live on Letterman series on April 12, 2011, performing songs from their Wasted Light album.

Foo Fighters most recently sat in for week-long residency on the The Late Show With David Letterman last October, when they previewed cuts from Sonic Highways -- a city-by-city concept album in which Letterman played a key early role. That visit was highlighted by a web-only video that found a clearly emotional Letterman talking about the band's 2006 song "Miracle."

“These gentlemen, we’ve known each other for a long long time now," Letterman said that night. "They have crossed my path in ways unexpected and expected. And, as a result, each and every year they grow to mean more to me as human beings and talents musical artists.”

"Miracle," Letterman said, had come into his life when a ski instructor paired it with footage of the late-night TV legend's young son on the slopes for a home video: “It’s the second song of theirs that will always have great, great meaning to me for the rest of my life.” Afterward, a teary-eyed Letterman said, “You see what I mean? That’s pretty good!”

Bob Dylan performed for a final time for Letterman last night, making his first visit to The Late Show since 1993. This closing run of musical guests has also included Tom Waits and Eddie Vedder.

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