Agatha: Coven of Chaos just added another Marvel veteran to its writer's room.

The Writers Guild of America West directory confirmed that Megan McDonnell, who wrote the third and fourth episodes of WandaVision and the script for next year's The Marvels, will be joining the Disney+ Phase 5 spinoff. This will mark another collaboration between her and Jac Schaeffer, who served as WandaVision's showrunner and wrote its first episode and season finale. Aside from her involvement in the Marvel Cinematic Universe, McDonnell's other credits include co-directing the 2016 short film Meet Cute and working on the upcoming Apple TV+ series Dark Matter.

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Initially titled Agatha: House of Harkness, Coven of Chaos will reportedly be produced using the Wizard of Oz-inspired working title "My Pretty." Aside from a focus on Kathryn Hahn's titular Agatha Harkness -- who Wanda Maximoff trapped in her "Agnes" sitcom persona at the end of WandaVsion's finale -- the spinoff's plot remains ambiguous. Filming on Coven of Chaos will take place next year between January and May, with an expected release date of Winter 2023.

It Was Agatha All Along

First introduced in 1970's Fantastic Four #94, Agatha Harkness is a centuries-old sorceress with in-universe connections to both Wanda and Franklin Richards. In addition to serving as the Scarlet Witch's magic teacher, Agatha was responsible for erasing Wanda's memories of her sons, Billy and Tommy, after learning that they were never real but in fact parts of the demon Mephisto's soul. Billy and Tommy's younger selves made their live-action debut in WandaVision but, despite massive speculation that Mephisto would appear as well, he never did. Instead, WandaVision's final episodes revealed Agatha to be the show's other major antagonist, having posed as a Westview, NJ, resident to study Wanda's reality-warping abilities and claim them as her own.

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Aside from Hahn and fellow WandaVision star Emma Caulfield Ford, Coven of Chaos has yet to announce its official cast. However, a casting call leak revealed that Marvel is looking to cast two gay male characters on Coven of Chaos, with their descriptions seeming to match that of an older Billy Maximoff and Teddy Altman/Hulkling. Since WandaVision, Marvel has introduced multiple characters from the Young Avengers superhero team through its various Phase 4 projects, including Kate Bishop, Eli Bradley, and America Chavez.

Furthermore, according to insider reports, Marvel may have cast Borat's Sacha Baron Cohen to play Mephisto, but not for Coven of Chaos. Instead, he will reportedly debut in next year's Ironheart series, which also features a supernatural antagonist in The Hood, played by In the Heights' Anthony Ramos. The show's protagonist, Riri Williams (Dominique Thorne), will make her MCU debut in next month's Black Panther: Wakanda Forever.

Agatha: Coven of Chaos is scheduled to premiere in late 2023.

Source: WGA