Warning! This article contains major spoilers for Agatha All Along episode 5. If you've not caught up yet, and don't want to know anything that happens, turn back now!
Agatha All Along dropped a bombshell on viewers in episode 5, when the Disney Plus series confirmed that Joe Locke's Teen is Scarlet Witch's son Billy. Now, in the run-up to episode 6, Marvel has revealed that he goes by 'Billy Maximoff', and the choice of surname has peaked fans' curiosity.
Wiccan, who we can safely assume Locke's Billy is due to his fluorescent blue powers, typically goes by 'Billy Kaplan' in the comics, having been raised by Rebecca and Jeff Kaplan. It's established throughout his run that he is a reincarnation of Wanda and Vision's son William Maximoff, while Tommy Shepherd AKA Speed is his long-lost twin brother. With that, fans are theorizing as to why Marvel didn't call him "Billy Kaplan" in the below social media post...
"They've cast a 'Rebecca Kaplan' as his mother. He'll be some version of Billy Kaplan, but they need to explain all this to people with zero comics context," someone claimed on Reddit, as another wrote: "They're probably calling him Billy Maximoff right now because the only reveal so far (and what Agatha knows) is that he's Wanda's son, not [his] whole backstory. I'm sure he's gonna be Billy Kaplan too, in some form."
Others disagree, with one user arguing: "They probs won't even mention Billy Kaplan, just Billy's soul inhabited the body of a dead Billy and now he's Billy Maximoff."
"I think this is good. It would be too confusing to introduce him as Kaplan to a normie. How would you explain it to a future movie audience? Keeping him Maximoff simplifies it greatly."
The theory that Billy's soul was absorbed by another isn't so far-fetched when you consider that the mid-season trailer sees 'Teen' getting into a nasty car accident. Agatha (Kathryn Hahn) briefly mentioned a crash in episode 1 of the WandaVision spin-off, and Joe Locke's name curiously appears over the top of a newspaper with the headline "near death in Westview" in the show's credits. Looks like the series is borrowing heavily from the comics, but twisting them slightly to make sense with the events of its predecessor.
Agatha All Along episodes 1 to 5 are streaming now. Ensure you don't miss a thing with our Agatha All Along release schedule. If you're keen to learn more about Billy's backstory, which involves mysteries, magic, and Mephisto, check out our in-depth explainer.
For more on the wider MCU, check out our guide to all of the upcoming Marvel movies and shows or get up to speed with our breakdown of the Marvel timeline.