The Simpsons to do its 'most musical episode' in season 33

The Simpsons will kick off season 33 by singing a new tune. Many of them, actually.

The long-running Fox animated comedy will present the 'most musical episode we have ever done,' the show's producers revealed in a Comic-Con video panel on Saturday. Titled "The Star of the Backstage," the Sept. 26 premiere is "almost wall-to-wall music,' said executive producer Matt Selman. "It's like a Broadway musical of an episode with all original songs."

In addition, The Good Place star Kristen Bell — who guest-starred in a season 27 episode — will be featured as Marge's singing voice. "We all love Marge's voice [Julie Kavner]," added Selman, "but this is the singing voice that's different, let's just say."

"Marge has amazing memories of being the stage manager of her high school musical, Y2K: The Millennium Bug, and decides to restage it with everyone 20 years later for one last show," Selman tells EW of the plot. "But when her old high school nemesis comes to town, she realizes that her high school memories aren't what she thought they were."

Selman also explained to EW in more detail how Bell factors into the story. "The only place Marge sang beautifully was in her head, so she has a magical inside singing voice that only we can hear," he says. "When she sings, it comes out beautiful, like Kristen Bell." As you might have noticed, the episode was inspired by the concept of Disney+ reality series Encore, which Bell hosted.

The Simpsons has dabbled in musicals and musical numbers over the years, including season 4's "Marge vs. the Monorail" and "A Streetcar Named Marge," season 5's "Homer's Barbershop Quartet," season 8's "Simpsoncalifragilisticexpiala(Annoyed Grunt)cious," season 12's "New Kids on the Blecch," season 15's "The President Wore Pearls," season 19's "Homer of Seville," season 22's "Elementary School Musical," and, yes, season 9's clip-show package "All Singing, All Dancing." "The Star of the Backstage" represents the show's most ambitious musical stab in that it is not a parody of an existing musical but a fresh story with all original songs, according to Selman. The episode was written by Simpsons writer-producer Elisabeth Kiernan Averick, who previously served as a writer and producer on Crazy Ex-Girlfriend. She co-wrote the lyrics with CXG composer Jack Dolgen, who wrote the music for this episode.

Meanwhile, back in the Comic-Con panel, exec producer Al Jean noted that this year's annual Halloween terror trilogy, Treehouse of Horror, will break form and feature five segments for the first time. (You can watch an Edward Gorey-esque segment in the video above.) In other fall episodes, "We have a romance that may come to stick in Moe's life, and we explore the greatest tragedy Homer ever faces with guest star Rachel Bloom," Jean said.

And for the fourth time ever, the show will unspool a two-part episode in the fall. Selman refers to A Serious Flanders as an "epic love letter to the show Fargo, prestige crime dramas, and the world of streaming television." Guest stars include Timothy Olyphant, Cristin Milioti, and Brian Cox. "It's like nothing we've ever done before, and I hope it makes sense," he quipped.

Watch the whole Comic-Con panel above, which includes a competition in which the writer-producers have to guess characters and key scenes as they're drawn by the animators.

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