Agatha All Along‘s fifth episode finally revealed the truth about Teen’s identity, but we had to wait another week for an answer to another mystery about him. “Familiar by Thy Side” explored the backstory of how Wanda Maximoff’s son Billy ended up transferring his consciousness into the late William Kaplan. That flashback included learning who placed the sigil spell on “Teen” in Agatha All Along. It was his own future Witches’ Road travel companion, Patti LuPone’s Lilia.
Why did a divination witch put a sigil spell on a boy who didn’t possess any magic just moments before he died and a witch took over his body? Lilia’s need to protect Teens’s future identity from Agatha and other witches reveals just how important the coven’s journey really is.
Lilia saw William Kaplan’s sad fate written on his hand. He was destined to undergo a great “transformation,” as his lifeline was broken in two. We soon learned that was literally true. Shortly after the palm reading William died in a car crash. Before anyone realized that, Billy Maximoff, who had just vanished with the collapse of his mother’s Hex in Westview, took over William’s body.
William didn’t know what really awaited him when he left Lilia’s booth. But she clearly knew more than she told him. Once he departed Lilia took out a small piece of wood. She drew a sigil spell on it and put it in William’s coat. That spell kept Billy’s true identity hidden from every witch throughout the show’s first five episodes. Once Lilia painted the sigil not even she could remember who he was, which is why she didn’t recognized “Teen” when he showed up with Agatha at Lilia’s door.
Lilia might be down on her luck, but she still possesses her powers of divination. She foresaw what would happen to William and that it would be important to keep Billy’s identity a secret from witches. (The sigil worked until Billy destroyed it himself.) What we don’t know is why Lilia knew it was important to keep his identity a secret. The fact she did shows that Agatha had to remain in the dark about his real name long enough for her to bring Billy and the coven to the Witches’ Road.
Something bigger than all of them is going on and, no matter if that’s good or bad, the coven’s divination witch foresaw they had to come together to address it. Lilia knew the only way to ensure they would was by placing a sigil spell on Billy in Agatha All Along.
What could be going on that Lilia foresaw they would all have to risk their lives alongside the least trustworthy witch in history on a Road only Agatha has ever survived? Our best clue might have come during poor William’s ill-fated palm reading. Lilia has been entering trance-like states and sharing cryptic prophesies throughout Agatha All Along. She can’t seem to control them or even understand them. Lilia shared one such omen with William: “The Tower reversed.”
What tower? Reversed how? Considering her prophecy and sigil were meant for Billy Maximoff and not William Kaplan, it’s hard not to think about how Wanda died. The Scarlet Witch brought the castle on Mount Wundagore down on herself. It was the tower of the Darkhold. That evil tome has been hovering in the shadows over all the events on Agatha All Along.
Could Lilia’s prophecy have something to do with that? Is that why it was so important to keep Billy safe long enough for Agatha to trust him? Why did Lilia want to make sure he reached The Road? Could Billy bring back not just his missing brother Tommy but his powerful mother as well?
Not even Lilia seems to know. Until Billy reaches the end of the Witches Road we probably won’t either. What we do know is that sigil spell was more important than we realized while it worked. It has been keeping Billy’s identity a secret. But it’s always been telling us just how important this coven’s journey really is.