Fans weren't the only ones hoping for more of Kathryn Hahn as Agatha Harkness when WandaVision ended more than three years ago.
"I was always interested in more Agatha," Jac Schaeffer, who created that series, as well as the new Agatha-centric spin-off, Agatha All Along, told Good Morning America.
Schaeffer said viewers' overwhelming response to Hahn's performance as the witchy breakout character -- and that viral song -- was a whirlwind ride, but a series focused on her "didn't seem within the realm of possibility."
The showrunner said a year or so after WandaVision ended, she was "exploring different characters and different worlds" for other Marvel projects, but she couldn't get Agatha out of her head.
"It just kept going back to her," she recalled, crediting Hahn. "The joy and complexity and the continued interest in this character is because of her."
Hahn called it "an actor's dream" to be able to embrace all aspects of her character -- from the dramatic to the kooky.
"I've been blessed enough in this career to be able to jump into different genres," she said. "I've never been really pigeonholed ... so I feel like this is, weirdly, the culmination of that ability."
As for whether or not Agatha is a true villain, Hahn and Schaeffer have a few thoughts.
Hahn said, "It feels very binary to call someone just bad" -- even Agatha.
"There is much more to explore there," Schaeffer said, adding that she also wouldn't call Agatha "evil."
"I think that as a young person she was told she was bad … and that kind of thing imprints on a person," she said.
Also starring Patti LuPone and Aubrey Plaza, Agatha All Along premieres with two episodes Sept. 18 on Disney+.
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