Buffy reunion: Sarah Michelle Gellar's singing voice was almost dubbed in 'Once More With Feeling'

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Nowadays it seems like everyone does a musical episode. But Buffy the Vampire Slayer was one of the first series to attempt the genre flip. Creator (and musical lover) Joss Whedon decided to have the supernatural series attempt their own musical hour in the otherwise bleak season 6. “Once More With Feeling” found Sunnydale under the spell of a demon that forced them all to croon their emotions.

While it’s widely hailed as one of Slayer’s greatest episodes, some of the cast members were, shall we say, a little hesitant about breaking out into song. Read on for what they told EW at the 20th-anniversary reunion.

MICHELLE TRACHTENBERG: The way I was told was Joss had been pitching it for ages and then all of a sudden Ally McBeal had a musical episode and Joss was like, “Hell naw!” On some weekends, Joss would have some cast members and crew and there would be a designated place and we would all read Shakespeare. Then afterward everyone would eat and drink. Then I think that James [Marsters] would get on the piano or Joss would get on the piano and I think that helped perpetuate the “Let’s do a musical!” episode.

SARAH MICHELLE GELLAR: I’m not a singer. I never have been and I didn’t have a lot of time with the material. So my original intention was to have someone else do the singing. What I didn’t realize at the time is it would be such an emotional arc for the character. I didn’t realize that would be the episode where you found out where she was. Then I talked to Joss and I said, “I don’t have the time and I don’t feel confident enough to do it.” We didn’t get the script until like two or three weeks before. I really went back and forth to whether or not I was going to sing. And Joss said, “I’ll do whatever I can to make it as easy on you as possible,” like bringing in my friend Adam Shankman. But it was exhausting.

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JAMES MARSTERS: I remember, in general for different reasons. I think the entire cast was a bit terrified. I think one person, I forget who it was, actually asked to juggle chainsaws instead. Like real chainsaws. And we didn’t realize how big of a genius Joss was. One of the recurring themes of working on that show over the years was just the slow dawning of the amount of talent contained in that skull of Joss Whedon. I think it was our best moment because at some point we knew that Joss would not be talked out of it and we definitely tried. And we stopped whining and we started working really hard. And suddenly there were voice coaches and dance coaches showing up on set. I think in the face of what we thought was certain doom, we decided to go out swinging. And I have said that for a bunch of Hollywood actors that’s as close to heroism as we’re gonna get.

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ANTHONY STEWART HEAD: “Once More with Feeling” was my dream because I got to do a musical on TV and it was genius. It was extraordinary. One of my fondest memories is once I had done my song, I hung around the studio because I didn’t want to leave. People kept coming in for their vocals and going, “Why are you here?”

NICHOLAS BRENDON: The musical for me was kind of my ultimate because it was so different. It didn’t matter if I sucked because I wasn’t hired to be a singer or dancer.