The annual Songwriters Hall of Fame ceremony is a one-of-a-kind event, a sort of cross between the Grammys and a trade-awards show, where superstars like Billy Joel meet equally great but near-anonymous songwriters like country great Bobby Braddock as peers. Each year, the show has a handful of moments you just won't see anywhere else: one year Joel and Garth Brooks wore matching Stetson hats to sing "Shameless" and, earlier, Drake performed a mixtape-only song "The Calm"; last year Miguel brought the house down with a torrid cover of the Gamble & Huff classic "Me and Mrs. Jones."

Yet the most surprising moment in many years took place on Thursday night, when Stephen Colbert made a totally unexpected appearance to induct country renegade Toby Keith. The pairing wasn't completely unlikely: Keith appeared on Colbert's show several times over the years, and while their affection for each other seemed genuine, it was the kind of bromance where viewers couldn't quite tell how in-character Colbert may have been.

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There was no questioning Colbert's sincerity on this night. Striding onstage in a black Stetson, black shirt and a denim jacket with white fur collar, he sang a convincing version of Keith's 2005 country chart-topper "As I Once Was" -- backed by the show's ace house band -- with characteristic combination of seriousness and irony, occasionally slipping into a jokey twang, stopping to look at his watch during the song's long pause before the last verse. When the song was over, he yelled "big dog!," whooped, and then walked over to the podium with a comic mock-cowboy swagger and delivered the following speech, portions of which were obscured by the crowd's laughter:

"Now, it is possible that people ask, 'Why the hell is Stephen Colbert honoring Toby Keith?' I don't know why they asked me to show up, but I'll tell you why I showed up. When Toby Keith was first on my show [crowd laughter obscures a few words] … said 'Listen to what this man was gonna say and sing, and I just might have a good time' -- and that was pretty much the reaction he had to Toby Keith: once you listen to what he has to say and sing, everybody has a good time.

"And my favorite part was of the night was, as the Big Dog was leaving out the stage door and I was going to the rewrite room -- this was very early on in my show and he didn't know what he was in for, I guess -- he turned around to me and he said, 'Hey man, you do a great job … whatever the f--- it is you do.'

"I was sincerely, deeply moved by that comment, so much so that my executive producer -- this is true -- had it stitched on a pillow for me for Christmas. [He holds up a pillow with those words stitched into it, a few words are obscured by cheering.] This is a man who rose from Oklahoma's oil fields -- where he worked on a rig -- and the state's football fields -- where he was a semiprofessional defensive end -- to become one of the most consistent hitmakers in country music for more than two decades. These days, the stamina of an oil rigger and the strength of an athlete are a definite advantage to making it in Nashville.

"With 46 No. 1 songs, 39 top tens and rooms full of platinum and gold albums, Toby the dynamic performer is unapologetically patriotic, opinionated, brash and often controversial, resonating legions of fans by writing up their lives in a very real way.

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"One thing we can agree about Toby is his songwriting talent: from 'Chug McGowan' to 'Beer for My Horses' to 'How Ya Like Me Now' to his upcoming album 35 mph Town, Toby Keith is an American classic whose songs resonate with family values.

"For instance, the song I just sang is the heartwarming tale of a man in a bar who has sex with two women -- who happen to be sisters. Family values [a few words obscured by laughter]. It is with great pride joy that I welcome Toby Keith into the Songwriters Hall of Fame!"

Keith then came onstage and began his long acceptance speech by saying, "I like to give people the finger a lot -- and you can't give the royal finger better than Stephen Colbert."