WARNING: The following contains major spoilers for Lovecraft Country Season 1, Episode 5, "Strange Case," which aired Sunday on HBO.

Lovecraft Country's latest episode makes a startling revelation about Christina and William Braithwaite. Ever since the characters were introduced on the HBO series, fans have seen the two siblings on their own, each working seemingly for the same goal, without ever sharing the screen together. And it turns out that was no accident because they are one and the same. The truth is William doesn't exist -- he is just a skin suit that Christina is able to wear thanks to her magic.

This means that whenever William appeared on the screen, it was actually Christina, simply taking on his appearance working to get what she wants. Her goal remains one of the big mysteries surrounding the character, but another piece of the puzzle is revealed when the episode reveals she has a connection to Hiram Epstein.

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In "Strange Case," William gives Ruby a magic potion that allows her to become a white woman. But this gift isn't a no strings attached deal because he also wants something in return, and it's Christina who later shows up to collect. She asks Ruby to appear at a Sons of Adam soiree held by Chicago Police Captain Seamus Lancaster, and to leave something in his office -- a magical artifact whose purpose has yet to be revealed.

As William, Christina tells Ruby that, once upon a time, he started working with Hiram Epstein. Epstein, as fans learned in "Holy Ghost," was the previous owner of Leti's new home, the Winthrop house. He was an astrophysicist who experimented on black people, torturing and killing them, all in the name of his scientific goal, which was to study the universe and create magical doorways to other locations.

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Christina has previously shown she is interested in getting her hands on an orrery that was supposed to be in the Winthrop house, a device that may contain the key to a time machine. It turns out she knows all of this because she worked with Hiram before -- more than likely as William.

If Christina was involved in those experiments, then it means she may have some knowledge about opening portals herself, but where she and Hiram were trying to go remains a mystery. It's possible they were interested in the Garden of Eden, a place Christina's father previously tried to reach. It's also possible Christina's interests lie further out in the cosmos because after all, the orrery is the model of a binary star system that may turn out to be Xoth, the birthplace of several cosmic beings known as the Ancient Ones.

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Christina may be after a time machine, but her connection to Hiram and his experiments means she could potentially open portals to other realities or dimensions. It's powerful magic, and it could end up playing an important part in whatever comes next.

Starring Jonathan Majors, Jurnee Smollett, Aunjanue Ellis, Abbey Lee, Jada Harris, Wunmi Mosaku and Michael K. Williams, Lovecraft Country airs Sundays at 9 p.m. ET/PT on HBO.

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