This whole time, as we’ve watched the first season of FOX’s “The Exorcist” unfold, we’ve been doing so with the notion that the Rance family’s story exists separately from the canon first created by William Peter Blatty, only to be continued in the 1973 film it inspired and the multiple sequels that movie spawned.

Yet, in Friday’s (Oct. 21) episode, titled “Through My Most Grievous Fault,” our whole world came crashing down around us. Angela Rance (Geena Davis) has been carrying around a very dark secret and, amid her family’s battle with darkness, it was finally brought out into the light.

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The episode delves into familiar territory, as the exorcism of Casey Rance (Hannah Kasulka) was reminiscent of the torture young Regan (Linda Blair) went through. It was only a matter of time before the demon taunted Father Tomas (Alejandro Herrera) and Father Marcus (Ben Daniels) with ghosts from their pasts. It’s a trick we saw Pazuzu do in the film and, much like the movie, the younger priest (Tomas) hits his breaking point and becomes compromised.

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So far, we’ve watched as Tomas battled temptation sparked by his married friend. And when Casey presents herself as Jessica (Mouzam Makkar) to the young priest, Marcus up and kicks him out. Of course, after kneeling before the Rance girl, he heads to Jessica’s house to commit adultery. It’s a necessary place for Tomas’ character to go as this is his rock bottom. And it’s during his plea for forgiveness, that he learns something very shocking about Casey’s mother, Angela.

Earlier in the episode, Casey whispers something to Henry (Alan Ruck) that sticks with him like the worst kind of ear worm. Continually questioning Angela about something she’s been keeping from him, we couldn’t help but think she had an affair while he was working through his mental injury. But instead, it turned out much more mind blowing.

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Up until this point, “The Exorcist” has connected to the original film through certain visuals and plot devices. But the true nature of the series has finally been revealed as Angela Rance tells Tomas about her own childhood trauma. Referencing the imaginary friend that came to her when she was a young girl — a little red bird — Angela admits to leaving her home town and changing her identity in the process.

Escaping her mother — and her past — has deemed futile, though. As Angela makes a startling confession: Her real name is Regan MacNeil. Yes, the same character that Linda Blair made famous — and for all intents and purposes, the demon inside Casey has really come here for her.

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“The Exorcist” airs Fridays at 9 p.m. ET/PT on FOX.

Posted by:Aaron Pruner

When he was a child, Aaron memorized the entire television lineup, just for fun. He once played Charlize Theron’s boyfriend in a Japanese car commercial. Aaron’s a lover of burritos and a hater of clowns. TV words to live by: "Strippers do nothing for me, but I will take a free breakfast buffet any time, any place."