Cobra Kai creators on how [SPOILER'S] surprise All Valley performance came together

Warning: This story contains spoilers for Cobra Kai season 4 episode 9, "The Fall"

How did Grammy-winning international superstar Carrie Underwood wind up singing an '80s anthem by Survivor in the penultimate episode of Cobra Kai season 4? The answer, readers, lies in this 16-month-old tweet:

Yes, Cobra Kai creators Jon Hurwitz, Josh Heald, and Hayden Schlossberg saw that tweet — and Heald jokes that they waited "about five minutes" to approach Underwood to discuss a possible guest appearance. (And don't worry, fans — the singer is aware that she spelled the title wrong.)

"Be careful what you tweet about Cobra Kai if you're a celebrity," adds Schlossberg, "because we immediately log it and think about the possibilities."

Season 4 of Netflix's Cobra Kai all leads up to the 51st Annual All Valley karate championship, which will determine the fate of the show's dueling dojos: Miyagi-Do, led by Daniel LaRusso (Ralph Macchio); Eagle Fang, led by Johnny Lawrence (William Zabka); and Cobra Kai, led by John Kreese (Martin Kove) and his old friend Terry Silver (Thomas Ian Griffith).

"We knew that we wanted this year's All Valley to be, like, the biggest All Valley ever, and we joked about the idea of there being that kind of Super Bowl halftime performer," says Schlossberg. Underwood "happens to sing the Sunday Night Football song, so it made a lot of sense. We didn't know if it was going to come together, but she really loved the show and it was a match made in heaven."

Says Underwood in a statement: "I grew up watching 'Daniel' and 'Johnny,' and I can't believe I actually get to be a small part of the legacy that is The Karate Kid. Once I discovered Cobra Kai a few years ago, it became one of my favorite shows! I had so much fun being on the set and singing such a classic song. I cannot wait to watch every new episode!"

After hyping up the crowd with a welcome speech ("I didn't see a lot of karate growing up in Oklahoma, but you guys know I love to compete, just like these wonderful young men and young women!"), Underwood launches into a performance of "The Moment of Truth," which the rock group Survivor released on the Karate Kid soundtrack in 1984. Fans may be wondering why Underwood didn't sing Joe Esposito's "You're the Best," which played during the original film's tournament sequence — and Schlossberg has a good explanation.

"A lot of people have asked us about 'You're the Best' and are we going to use that? We felt that if we just did that song, it would just be a copycat of what the movie was," he says. "We love this song 'The Moment of Truth.' It's a little bit less known, and yet it still has that same 1980s sports-rock anthem vibe. So to have her sing that, it gave that same vibe to the tournament without doing the exact same thing."

For more on Cobra Kai season 4, read our full digital cover story here.

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