WandaVision's Kathryn Hahn on That Agnes Theory: Is She Really [Spoiler]?

The truth behind WandaVision‘s strange sitcom universe is still shrouded in mystery — and Marvel fans have concocted plenty of theories in the meantime.

As the Disney+ series ever-so-slowly reveals how Wanda and Vision came to be in Westview, viewers have speculated on just about every aspect of their retro TV world, including the real identity of Kathryn Hahn‘s nosy neighbor, Agnes.

More from TVLine

• New WandaVision Trailer Teases a Game-Changing Episode 4: 'Nothing Can Prepare You for What's Next'

• WandaVision's Emma Caulfield Talks Dottie's 'Surreal Moment' — Plus, Did the Writers Sneak in a Buffy Reference?

• WandaVision's Kat Dennings Tees Up a Darcy That Has 'Not Been Seen Before'

The leading theory? Agnes is actually — spoiler alert, just in case! — Agatha Harkness, a skilled witch who, in the Marvel comics, trains and mentors Wanda in using her powers. The show has yet to explicitly indicate that Agnes is really Agatha outside of the sitcom world, beyond Agnes’ name as an obvious portmanteau of “Agatha Harkness.”

As Hahn tells TVLine, she’s aware of the speculation about her character — and though she can neither confirm nor deny Agnes’ real identity, she hints that the truth about her character might not be what fans are expecting.

“I can safely say that there are so many levels of surprises, and so many layers, that people will not see coming,” the actress teases. “I am just so excited for fans — and people that are new to this world — to go on the ride. It’s just a real, multi-level trip, and I’m so excited for people to go on the journey.”

A new trailer for Episode 4 (releasing Friday, Jan. 29) offers the biggest answers yet about Wanda and Vision’s alternate reality in Westview: Among other clues, there’s a quick glimpse of the S.W.O.R.D. agency’s ongoing research, which confirms that nearly every Westview resident has a different identity in the outside world, complete with present-day New Jersey driver’s licenses for each person. Interestingly, though, Agnes’ photo is on the wall without a corresponding ID card, while Emma Caulfield’s Dottie is missing from the board altogether.

Best of TVLine

• Vampire Diaries Turns 10: How Real-Life Plot Twists Shaped Everything From the Love Triangle to the Final Death

• Vampire Diaries' Biggest Twists Revisited (and Explained)

• Everwood Turns 15: The Creator, Stars Recall Braving Freezing Temps to Deliver the Pilot's Emotional Fight

Get more from TVLine.com: Follow us on Twitter, Facebook, Newsletter