Warning: This article contains spoilers for Agatha All Along episode 4, “If I Can’t Reach You/Let My Song Teach You”

Agatha Harkness and Rio Vidal clearly have a very intense history in Agatha All Along, and episode 4, “If I Can’t Reach You/Let My Song Teach You,” reveals more about their mysterious relationship in the MCU. The connection between Kathryn Hahn’s Agatha Harkness and Aubrey Plaza’s Rio Vidal has been a hot topic of discussion since Agatha All Along’s premiere ended with their heated spar. After being absent for episodes 2 and 3, Rio Vidal returned in episode 4, controversially replacing Sharon Davis in Agatha Harkness’ coven on the Witches’ Road.

Following their brief fight in Agatha All Along episode 1, “Seekest Thou the Road,” speculation began to stir regarding a possible romantic relationship between Agatha Harkness and Rio Vidal. Their intimate spar certainly implied some personal connection in their past, but the series hasn’t yet revealed exactly what this connection entailed. Agatha All Along episode 4 uncovered more details, however, confirming huge details about Agatha Harkness and Rio Vidal’s history in the MCU that will surely have an impact on the series’ upcoming episodes.

Agatha Harkness’ Relationships In Marvel Comics Explained

Agatha Harkness Has Seldom Had A Romantic Relationship In Marvel Comics

Marvel Comics’ Agatha Harkness, first seen in 1970’s Fantastic Four #94, has seldom been depicted with a love interest. However, since her debut, Agatha Harkness has demonstrated a maternal, caring and generous personality, first as the governess to Franklin Richards and a companion to the Fantastic Four, and later as a mentor and mother-figure to Wanda Maximoff’s Scarlet Witch. The existence of Nicholas Scratch, Agatha Harkness’ powerful and villainous son, confirms that, at some point, the witch has been embroiled in an affair of the heart.

In fact, in Marvel Comics, Nicholas Scratch was the consequence of Agatha Harkness’ marriage, though the identity of Scratch’s other parent has never been confirmed. Since Nicholas Scratch is an amalgam of euphemistic names for the Devil (Old Nick and Old Scratch), some have speculated that the demon Mephisto could be his father, which may lend weight to theories concerning Mephisto’s upcoming MCU debut in Agatha All Along. Rio Vidal currently has no Marvel Comics counterpart, so her connection to Agatha Harkness in the MCU is brand-new and very exciting.

What Agatha All Along Episode 4 Reveals About Rio & Agatha’s Relationship

Agatha All Along Episode 4 Confirmed A Romantic Past For Agatha Harkness

Prior to Agatha All Along episode 4, not much was known about Agatha Harkness’ history with Rio Vidal, but that is no longer the case. Most notably, episode 4 confirmed that Agatha Harkness and Rio Vidal had been romantically involved long before the series kicked-off. This comes after the cast of Agatha All Along claimed the series would be “the gayest project Marvel has ever done,” and, hilariously, a “gay explosion” (via Variety). This is a very enticing development, but Agatha All Along episode 4 also revealed some dark truths about Agatha and Rio’s relationship.

Sasheer Zamata: You’ll see when you watch. Witches are queer, inherently, just because we are outcasts and set aside for many reasons. This show shows a really good representation of different types of people and that we can all use the power we have within to go forward and be great.

Joe Locke: It’s got many layers and gay is one of them. That’s one of the great things about the show… “Teen” is a queer guy on the show, but it’s not the driving force, which I think is really great. It’s really nice to just have these positive queer characters.

Kathryn Hahn: What is the most exciting thing about it is that’s not exactly what it’s about. It’s so normalized.

Aubrey Plaza: It will be a gay explosion by the end of it.

Ali Ahn: It is the gayest show on Marvel… There is a lot of pageantry we’re already competing with. I think the thing that makes it more gay is that we are singing with Patti [LuPone].

According to Agatha Harkness in the sound booth of the second house on the Witches’ Road, she and Rio Vidal used to work together. However, as revealed by Rio Vidal around the campfire, she was eventually forced to “do [her] job,” but this marked an act of betrayal against Agatha Harkness, hurting her and destroying their romantic relationship irreparably. Agatha All Along episode 4 overtly supports recent popular theories suggesting Rio Vidal may actually be Lady Death, hinting at an incredibly dark and twisted past for both Agatha Harkness and Rio Vidal.

How Rio & Agatha’s Relationship Reveal Changes An Episode 1 Scene

Agatha Harkness & Rio Vidal’s Episode 1 Fight Has New Meaning Now

Agatha All Along episode 1 ended with Rio Vidal bursting into a reawakened Agatha Harkness’ home. However, Agatha claims Rio is “not allowed” to kill her, perhaps suggesting the pair may have exchanged vows, possibly even in a marriage ceremony. Theories of Rio Vidal being Lady Death explain Agatha’s animosity toward her, as her lover would have been forced to take Agatha’s son, contributing to the brutal act of betrayal. The intensity and heat of this fight is fully explained thanks to Agatha and Rio’s past romance, and anticipation is high for Agatha All Along to develop it further.

New episodes of Agatha All Along release every Wednesday at 6pm PT/9pm ET on Disney+.