'Agatha All Along' creator Jac Schaeffer still can't believe she conjured up Patti LuPone

The fourth episode of Marvel Television's WandaVision spin-off Agatha All Along drops Wednesday at 9 p.m. ET on Disney+.

The show's creator, W/V alumna Jac Schaeffer, tells ABC Audio she's still pinching herself over the cast, which includes Kathryn Hahn reprising in the title role of Agatha Harkness, but also her fellow women of the witchy persuasion Sasheer Zamata, formerly of Saturday Night Live; Parks and Rec favorite Aubrey Plaza; and Broadway legend Patti LuPone.

The latter "get," Schaeffer tells ABC Audio, seemed impossible.

"With Patti, it was suggested and I was like, 'She's not gonna to do it,' And then ... you know, we heard through agents and stuff that she was open to it. And I was like, 'That's not happening.'"

Schaeffer continues, "And then they told me I had a Zoom with her, and I was like, again, 'This is not a thing that happens in the world.'"

Her doubting aside, Schaeffer said LuPone immediately sparked to her eventual role, 450-year-old Sicilian witch Lilia Calderu. "I got on with her and I said, 'You know, you'll be playing a witch.' And she said, 'Well, I am a witch.'"

Laughing, Schaeffer said, "And, like, you believe that when Patti LuPone says that to your face!"

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