An especially memorable moment in Marvel's WandaVision came when Kathryn Hahn's villain Agatha got her own theme tune, "Agatha All Along." Fans have been humming the earworm ever since, but the first one to latch onto it was Hahn herself.

Four stars of the show, as well as executive producers Jac Schaeffer and Matt Shakman, discussed the conception of the song in an interview with EW. Describing the winning tune as the "Munsters meets Oompa-Loompa song," they went on to recall asking each other, "Would Kathryn sing it?" and immediately deciding, "Oh yes, yes she will."

RELATED: Paul Bettany Reveals which WandaVision Scene Terrified Him

Hahn was in complete agreement. "I was like, if anybody else touches it, I'm gonna be so angry," she said. "Like, I was like, 'I have to do it. I have to do it.' I was so excited."

In WandaVision's seventh episode, "Breaking the Fourth Wall," it is revealed that Wanda and Vision's nosy neighbor Agnes is the witch Agatha Harkness, and that the tragicomic problems that have been plaguing Westview were her own doing. Agatha openly takes credit for the mayhem in the lyrics of her catchy jingle, which was soon rising in the charts to surpass major music stars like Justin Bieber, and even generated its own line of "Agatha All Along" merchandise.

Speaking about the delight she took in her brief stint as a rock star, Hahn joked, "When I am, God willing, a very very old lady, I will be able to just be rocking in a chair on a porch, remembering that I was above the Biebs for a very short amount of time."

RELATED: WandaVision's Cut Therapy Scenes Were Necessary and Should Have Stayed In

Hahn's over-the-top performance as Agnes/Agatha went beyond her vocal talents. At the end of the song she winks and bursts into evil laughter, a moment which "has taken on a whole life" in memes and pop culture references. Asked whether she wants to own it, Hahn replied, "Yes! What else can you do? I'm super flattered."

Written by Jac Schaeffer and directed by Matt Shakman, WandaVision stars Elizabeth Olsen as Wanda Maximoff/Scarlet Witch, Paul Bettany as Vision, Randall Park as Agent Jimmy Woo, Kat Dennings as Darcy Lewis, Teyonah Parris as Monica Rambeau and Kathryn Hahn as Agnes/Agatha Harkness. The series is available to stream on Disney+.

KEEP READING: Knives Out 2 Adds WandaVision Star Kathryn Hahn

Source: Entertainment Weekly