The following contains spoilers for The Guardians of the Galaxy Holiday Special, now streaming on Disney+.

Marvel shared a clip from The Guardians of the Galaxy Holiday Special, featuring a sing-a-long of the original song "I Don't Know What Christmas Is (But Christmastime is Here)."

The video features the alt-country band Old 97's as a group of alien musicians who attempt to make sense of Peter Quill's confusing Yuletide lore. Writer/director James Gunn discussed writing the song with frontman Rhett Miller, saying, "I had all these lyrics for it, and it kept changing. I walked around my house, singing into my iPhone and trying to figure out how the song was going to work. And finally, I approached Rhett and asked, 'Will you help me write this song? Because I can't do it by myself.' And he said, 'Absolutely.' And so we started sending tons of recordings and lyrics back and forth, and we wrote that song together."

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Like the first two Guardians movies, the Holiday Special boasts a soundtrack of retro hits curated by Gunn himself -- this time being a collection of Christmas songs. In addition to "I Don't Know What Christmas Is," Old 97's recorded a new version of their song "Here It Is Christmastime" with Quill's hero Kevin Bacon on lead vocals. Bacon shared his excitement about being part of the musical moment, saying, "I love the Old 97's song. It's really hard to write a new Christmas song, and I think it's got a really nice combination of sweetness and sentimentality without being a corny take on Christmas. And it rocks, and I loved it."

The Holiday Special Sets Up Guardians of the Galaxy 3

Gunn said he'd been planning to make the Holiday Special since before the release of Guardians of the Galaxy Vol. 2 in 2017. Additionally, he used the Holiday Special to "Trojan horse" story details for the upcoming third Guardians of the Galaxy movie, explaining some of what the Guardians have been up to since their appearances in Avengers: Endgame and Thor: Love and Thunder. Among the new details are the team's base of operations in the space station Knowhere, their new ally in Cosmo the Spacedog and the revelation that Mantis is Quill's sister.

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Guardians of the Galaxy Vol. 3 is set to be the end of Gunn's tenure with these characters and potentially the darkest chapter of their story yet. However, Mantis actor Pom Klementieff has said that it may not be the last fans see of Marvel's cosmic heroes. "It's gonna be, in some ways, the end of a chapter, you know? As the Guardians of the Galaxy family," she said. "So we'll see what happens after, it's not like, 'over, over,' but it's gonna be different after, for sure."

The Guardians of the Galaxy Holiday Special is available to stream on Disney+.

Source: YouTube