[This story contains spoilers for season four, episode seven, of USA Network's Mr. Robot, "407 Proxy Authentication Required."]

Mr. Robot (Christian Slater) and Elliot Alderson (Rami Malek) are one and the same. Darlene (Carly Chaikin) is Elliot's sister. Elliot spent most of the second season in an illusory world designed to mask his imprisonment. In addition to Mr. Robot and Elliot, there may be an "other one."

These are just a few of the staggering revelations found throughout Sam Esmail's USA Network thriller, which focuses on a computer hacker's crusade against the most powerful people on the planet — and yet, all of these revelations pale in comparison to the one at the heart of Sunday's "407 Proxy Authentication Required," in which a central trauma from Elliot's past is revealed: He was sexually abused by his father as a child.

Written and directed by Sam Esmail, "407 Proxy Authentication Required" plays out as a commercial-free, five-act stage play starring four major players: Elliot, Robot, the villainous Fernando Vera (Elliot Villar) and Elliot's therapist Krista (Gloria Reuben). Vera wants to recruit Elliot as a partner, in a drugged-out plan to conquer New York City. He uses Krista's safety as leverage in his attempt to win Elliot over. What's more, he wants to break Elliot, opening his eyes wide to his own truth.

In that effort, Vera forces Krista into conducting a therapy session with Elliot. At first, it's a reluctant paint-by-numbers back-and-forth. Soon, it takes a tragic turn, when the nature of Mr. Robot's existence is called into question. Krista pushes in on one of the most formative moments from Elliot's life, not to mention one of the most mysterious events of the series through four seasons: the long ago wintry day Elliot fell out of a window as a child. Robot, who manifests to Elliot in the image of his father, Edward Alderson, insists he was created to protect Elliot. But as Krista guides Elliot into remembering the actual events of the day, a beleaguered Mr. Robot walks away, telling Elliot: "I can't protect you anymore." In what's easily one of Rami Malek's single most powerful performances of the series, not to mention the single most upsetting scene of the entire show, Elliot tearfully recalls the truth: He jumped out of his bedroom window to escape his father, a sexual abuser.

The final act of the episode sees Vera trying to bond with Elliot over their shared history of abuse as children. Krista breaks that bond by stabbing Vera in the back, killing the man, closing the episode in darkness. A title card at the end of the hour calls viewers' attention to information for the National Domestic Violence Hotline: 1-800-799-7233 and thehotline.org.

Devastating. That's one word to describe the episode. And yet it does not feel nearly sufficient in articulating the severity of the revelation that Elliot was sexually abused by his father. It completely recontextualizes Mr. Robot. The first scene of the entire series sees Elliot busting a man responsible for operating a child pornography website, as one example. The third episode of the series features a memory of Elliot with his mother, talking about his recently deceased father. "He was weak and pathetic," she tells her son. In the ninth episode, Elliot remembers taking trips into New York from New Jersey, and mentions picking out the statistically safest train cars on the way into the city, and the least safe on the way back: "I hated going home." It fully recolors every fond interaction between Elliot and Edward, the Back to the Future photos, the trips to the movies.

"I wish I had been a better father to you," Edward tells his son in the opening scene of season three's powerful eighth episode, "Don't Delete Me." "All I'm asking is you forgive me. Do you think you'll ever be able to do that?"

"No," Elliot responds. Moments later, Edward collapses in a coughing fit; it's unclear if this is when he dies, but Elliot walks away from his fallen father all the same, stopping only to pick up his Mr. Robot jacket. He walks into a mostly empty theater, wearing the coat, and he whispers to an empty seat next to him: "Shh. The movie's about to start."

Those are just a few of the examples of how Edward as an abuser changes everything we know about Mr. Robot. Look back through the series; so many more examples doubtlessly, inevitably and tragically emerge.

Behind the scenes, the episode itself lives up to its title, "Proxy Authentication Required." Actor BD Wong tweeted about the episode: "At the table read, any actor who's character wasn't in it was asked to leave the room." In addition, creator Sam Esmail declined to speak with The Hollywood Reporter about the episode, opting to let it speak for itself.

Much earlier in the season, following the premiere episode, THR spoke with Esmail for the Series Regular podcast, asking about how the ending of the series matches the ending he originally envisioned when Mr. Robot was first planned as a feature film. This was his response:

"The themes and the specific ending is what I pictured the feature film ending of this as. But I have to say, the thing that turning it into a series did for me for what I originally envisioned with this story is we've created all of these wonderful characters around Elliot. I think his journey means more because of those relationships. It's funny. The feature version was about this loner. I don't think by the end of that movie version, he ever really connects with anyone. Thankfully, adapting it to the TV format, I was able to actually have characters pair up with him and challenge him and engage with him and I was able to explore a way for this guy to not just arc to the ending I had in mind, but along the way, develop relationships I did not think this character should or would have had in the movie version. In a lot of ways, even though the ending is the same, I think his journey is going to be much deeper and more satisfying, because of the other characters circling him."

A sentence from Esmail that stands out: "In a lot of ways … the ending is the same." It matches up with what Esmail told THR about "the other one" reveal from the final season's second hour, in which it's hinted there may be a third personality lurking within Elliot. Esmail said the twist was baked into the series from the very beginning, and would recolor the entire viewing experience. In the delivery of that twist, it's important to remember Mr. Robot said he did not remember Darlene telling him about the return of Fernando Vera, leading to questions about a third personality — but that was assuming Robot was no longer lying to Elliot. In "407 Proxy Authentication Required," Robot stood between Elliot and the truth about Edward Alderson for as long as he possibly could, showing he was still willing to lie to Elliot to keep him away from the pain of his childhood abuse; did he lie to Elliot about Vera's return, sensing the path to this awful truth coming to light?

In evaluating "the other one," then, perhaps it's not a question about Elliot, Mr. Robot and a third personality. Let's re-evaluate the dialogue from that stunning boardroom scene between Elliot as a child and his mother, both of them presumably lurking within the recesses of Elliot's mind:

Magda: "I've been looking all over for you. You shouldn't be sitting there, that's not your seat."

Elliot: "Why? I thought …"

Magda: "They're not ready yet. We need to wait."

Elliot: "For what?"

Magda: "For him."

Elliot: "You mean Mr. Robot?"

Magda: "No."

Elliot: "Elliot?"

Magda: "No … the other one."

Is "the other one" Edward Alderson? Is the meeting of the minds we're building toward Elliot having to confront the reality of his father, the person whom he long viewed as his "only friend," only to now realize the tragic, monstrous truth? Theorize as you wish, assuming you have the stomach for theories at the moment. Whatever answers lie in the future, for now, we're left to reflect on how this tragic revelation changes everything seen on Mr. Robot thus far, and grieve alongside Elliot accordingly.

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