Joe Locke’s ‘Agatha All Along’ Character Identity: All The Clues

SPOILER ALERT: This piece contains spoilers for the first five episodes of Agatha All Along.

Joe Locke’s mysterious goth “Teen” in Agatha All Along marks quite a shift in character from his Heartstopper role of Charlie Spring.

The young British actor made his Marvel Cinematic Universe debut alongside in Agatha All Along when the series premiered with two episodes Sept. 18. Showrunner Jac Shaeffer has teased a fun buildup to finding out the true identity of Locke’s character.

A frenzy of theories online, which are laid out below, overwhelmingly point to a certain character in the Marvel comics. Turns out, they were correct. Joe Locke is playing Billy Kaplan aka Wiccan, the Scarlet Witch’s son.

Read on for all the Easter eggs that led to Teen’s identity reveal and more clues about what he might want with Agatha and the Witches Road.

Episodes 1 & 2 – “Seekest Thou The Road” & “Circle Sewn with Fate Unlock Thy Hidden Gate”

Within the first two episodes, it becomes clear that Teen won’t be able to divulge any details as to who he is. When Agatha (Hahn) asks Teen his name in Episode 2, he says it, but a sigil that appears to be in the shape of a cursive capital ‘M’ covers his lips when he says the word. The most common theory is that Teen is Wanda’s son Billy Kaplan, aka Wiccan, and the ‘M’ could stand for “Maximoff.”

His voice also sounds muted to Agatha in the car when she asks him where he’s from. She can hear the radio just fine, but his voice cuts out completely. Also on that car ride, Teen’s boyfriend (who could be Teddy Altman from the comics) calls him because “he worries.” Billy is one of few openly gay male Marvel characters.

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It’s important to note that Teen is the one who snaps Agatha out of the hex Wanda left behind on Westview, trapping the witch in her false role of nosy neighbor Agnes when she snuck into the dream world Wanda built. He is an amateur witch, and he arrived shortly after Aubrey Plaza’s Rio Vidal made her grand entrance, which muddles a bit what magic in the questioning room was his or hers. Photos of the woman’s dead body Agnes saw in Episode 1 changed to flowers, and a painting appearing on the mirrored wall.

Episode 3 – “Through Many Miles/Of Tricks and Trials”

It’s not until Episode 3 that Agatha’s chaotic coven notices that “someone’s put a sigil on the boy.” The sigil, or magical seal, takes the form of a cursive capital M. Lilia Calderu (Patti LuPone) points this out, and it’s the first time Teen realizes he’s under the spell as well.

Episode 5 – “Darkest Hour, Wake Thy Power”

His identity is revealed in the final moments of Episode 5, when his powers overtake him after a trial that leaves Alice dead.

After becoming incensed by Agatha’s taunting, Teen’s blue magic begins to crackle from his fingertips, and he sics Jen and Lilia on Agatha, possessing them to toss her off the Witches Road. Then, he tosses the two of them off the Road as well, and all three are sucked into the earth. Cut back to Teen, who is now donning a blue crown that looks just like his mother’s.

Any theories that Teen could be Agatha’s son, Nicholas Scratch, are dispelled when he can fully say the name without the sigil blocking his lips. Rio also told Agatha that he wasn’t her son in Episode 4.

Still, there’s no telling what he’s doing on the Witches Road or why he sought out Agatha’s help. It’s also not entirely clear yet whether he’s purposefully trying to hurt Agatha, Jen and Lilia by forcing them off the road. Billy’s powers are very similar to his mother’s, so it makes sense if he might get a little lost in them in heated moments, much like Wanda has.

The Trailer:

A big connection many viewers pointed out prior to the series launch is a specific outfit Locke wears in a scene in one of the trailers for Agatha All Along.

A shot of Locke wearing clothes very similar to an outfit young William ‘Billy’ Maximoff wore in WandaVision. The below character poster also depicts the costume. Turns out, this shot is from Episode 5, during the trial, shortly before his Wiccan reveal.

In the comics, Billy has powers very similar to his mother Wanda’s — chaos magic, telepathy and other electric powers, which viewers got a glimpse of in the final episodes of WandaVision.

Who is Mephisto?

Another theory is that the sigil belongs to Mephisto, which could either solidify the theory that Teen is Billy, or it could be setting the stage for Teen to be the son of the red demon. In the comics, Wanda created her twin sons from two lost souls that Mephisto “lent” her.

Mephisto is a master manipulator and a big bad in the comics, and he returned to claim the souls of the boys when Wanda gave them up, but the souls were so influenced by Wanda that they vanquished the demon and were reincarnated elsewhere. Billy became the son of Jeff and Rebbecca Kaplan in New York City, later renaming himself Wiccan after he took the title Asgardian for a bit. Wiccan became a young avenger alongside Kate Bishop and Cassie Lang.

In the third episode, Jenn (Sasheer Zamata) drops the name Mephisto as the coven visits a luxury beach house for their first trial, which turns out to be for her — the potions witch. This isn’t in reference to the Teen’s identity, but rather that of Agatha’s son, who — Jenn tells Teen — was traded by Agatha for the book of the damned (The Darkhold). This comes after Jenn warns Teen to be careful of Agatha because of the rumor that she traded her own child for the darkhold, and this was referenced in a previous episode with the words “another child sacrifice?” in regard to Teen.

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Agatha Harkness’ son Nicholas Scratch grew up to be a powerful warlock in the comics, and he did become an agent of Mephisto after getting banished to Hell where he agreed to serve the red demon.

“They say that nobody really knows what happened to him,” Jennifer says. “They say he might be dead. Others say he might be a demon or an agent of Mephisto. But hey, that’s what happens when you have Agatha Harkness as your mom. I doubt she’d even recognize her own son if he showed up on your doorstep.”

Later, while bonding with Alice (Ali Ahn), Teen confesses “A lot happened to me at 13 too,” which could reference a few things based on who he really is.

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In Episode 2, the “Black Heart” that was on the list of witches Agatha needed to form her coven led her to ask Mrs. Hart aka Sharon Davis (Debra Jo Rupp), who joined as the missing green witch to perform necessary earth magic. But, the clue also called back to Rio Vidal’s self-described “black heart” that beats for Agatha.

Well, interestingly enough, Blackheart is a character in the Marvel Comics. In fact, he is the son of Mephisto. From the way Rio Vidal described her own heart, some think she could represent the gender-swapped child of Mephisto with a probable connection to the Teen, as she did appear in Westview around the time that Teen came looking for Wanda. If Rio is Blackheart, it makes sense she might come looking for Wanda’s son.

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However, Teen himself could also be Blackheart as well. As endearing as he is, there’s no telling if Teen has an ulterior motive for requesting Agatha’s guidance walking the Witches Road.

All signs are pointing to the fact that Mephisto is likely on his way, because, in the same trailer noted above where we spot a Billy-esque outfit on Teen, a suspicious fiery figure who looks a lot like the demon appears in the end.

Now that episode 4 has arrived, those who have seen will know that this creature wasn’t Mephisto, but rather a manifestation of a generational curse on Alice and her mother Lorna Wu. Still, more hints arrived at the end of the show’s fourth episode as to Teen’s true identity. Agatha confessed that she wouldn’t know if she put the sigil on him because it would work on her even if she was the one who cast it.

Rio Vidal, who joined the coven as the replacement green witch in Episode 4, also told Agatha that Teen was not “hers.”

Baron Mordo

Mordo is also a consideration because of his Sorcerer Supreme status in one universe, as seen in Doctor Strange in the Multiverse of Madness (2022). In the film, which sees Wanda as a villain, Mordo (Chiwetel Ejiofor) as Sorcerer Supreme in one of the many multiversal dimensions, trapped Doctor Strange and America Chavez at the Illuminati Headquarters. Wanda used the darkhold to dreamwalk into her self in that universe and slayed the four illuminati — Captain Carter (Haley Atwell), Black Bolt (Anson Mount), Captain Marvel (Lashana Lynch), Reed Richards (John Krasinski) and Professor X (Patrick Stewart) — leaving only Mordo to survive.

Mordo is the least likely theory of the caster of the sigil because Teen’s shrouded identity must be making way for the introduction of a character, whether it be his future Young Avenger self or Mephisto or even to bring Wanda back. Mordo’s connection to Wanda from their previous encounter could motivate him to want to hide Billy and Tommy from her if she is somehow still alive and searching for them.

There exists a deleted scene from Multiverse of Madness where Wanda kills Mordo, so the fact that they chose to leave that out and keep him alive is an interesting clue.

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