Agatha Harkness could be the best possible choice for WandaVision's big bad. Marvel Studio's first series to arrive on Disney+ has been full of twists and turns, encouraging its audience to unravel the mystery that lurks ominously in every corner of Wanda's sitcom-inspired world. In the discourse, there have been no shortage of theories as to who is behind the trauma inflicted on Westview and its residents. For many, Mephisto (Marvel's Satan stand-in with ties to Scarlet Witch in the comics) has been the prime suspect.

However, WandaVision episode 7 makes a compelling case for Agnes, who at long last was officially revealed as "Agatha Harkness," Scarlet Witch's mentor and sometimes-antagonist from comics lore. In the show, Agnes/Agatha has had a compelling presence, bolstered by Kathryn Hahn's multi-layered and charming performance. Agatha has always been a little too interested in Wanda and Vision's suburban life and hovered a bit too closely over their twin boys. But in this newest WandaVision chapter, Agatha's creepiness reached new heights. After stumbling upon a vine-covered and ancient-looking room (complete with witchy paraphernalia), Wanda is joined by Agatha, hair now unkept and holding her pet rabbit Señor Scratchy. "Wanda, Wanda, Wanda...," she tuts. "You didn't think you were the only magical girl in town, did you?" In that moment, Agatha is a chilling combination of Winnie Sanderson and Hannibal Lecter.

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In addition to being played by an actor clearly capable of the necessary scenery-chewing, revealing Agatha Harkness as WandaVision's primary antagonist makes sense, at least in terms of the show's narrative. Agatha has been involved in the story all along, making all of her actions and cryptic lines all the more deliciously devilish on a rewatch. Many have suggested that someone else (like Mephisto or Nightmare) may be pulling Agatha's strings and, while this could end up being true, the show runs a serious risk in introducing such a figure so late in the story. As with all mysteries, part of the fun lies in the unraveling and the creators not "playing fair" with its audience may undercut what has been a very engaging puzzle.

Kathryn Hahn as Agnes Agatha Harkness Agatha All Along WandaVision

Looking at the broader scope of the MCU, there is also the risk of introducing an A-list villain too early. Since figures like Mephisto (and Nightmare for that matter) have canonical ties to so many of Marvel's heroes, the larger MCU may be better served to keep such an imposing villain in the shadows for a while longer. Thanos, after all, loomed throughout the Infinity Saga in the run-up to Avengers: Infinity War, but always in the background while other antagonists challenged our heroes and forced them to grow. Since WandaVision has been a more intimate exploration of Wanda's character, using a villain tied more closely to her story would ultimately serve the show and its central character more effectively.

Agatha Harkness, a fellow witch and magic-user, has the potential to expand understandings of both Wanda and the MCU's mysticism, which will surely be crucial to Phase 4's larger story, and potentially continue to have an impact on the MCU through Phase 5 and beyond. In interviews, Kevin Feige has said that Wanda Maximoff will finally adopt her "Scarlet Witch" moniker in WandaVision, acknowledging that the character's powers have never been directly attributed to magic in the films. WandaVision has already taken steps to identify Wanda as a witch of sorts, showcasing her new reality-bending powers, hearing her threaten to "magic" the imposter Pietro into a "pickled herring," and being called a "magical girl" by Agatha. Since we know Wanda is set to appear next in Doctor Strange in the Multiverse of Madness, Agatha is sure to help - in one way or another - tease out some of her new magical abilities.

In WandaVision episode 7, Wanda, conversing with Monica, wonders if she really is a villain. That has been a central question throughout the show so far. Up to this point, WandaVision explored the trauma and grief inflicted so brutally on Wanda during her life and watched as she teeters between "good witch" and "bad witch." With Agatha as a foil and an example of a powerful sorceress corrupted by power, Wanda may see a future for herself she must fight to prevent.

Next: WandaVision: Every MCU Easter Egg In Episode 7

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