[Warning: This story contains spoilers from episode nine of HBO's Westworld.]

"That doesn't look like anything to me."

When Bernard Lowe (Jeffrey Wright) first uttered these words at the end of "Trompe L'Oeil," a horrible truth burst to light: The Westworld programmer actually was programmed by Robert Ford (Anthony Hopkins) and is a host walking among humans. Little did he (or viewers) know at the time that there was an even bigger secret at play: As revealed in the season's penultimate hour, "The Well-Tempered Clavier," Bernard isn't just any ordinary host, but a host based on the park's mysterious co-founder Arnold.

It's a complicated development, one that's only complicated further in the way the information comes to light. As Bernard trips down memory lane toward remembering his very first day online, Dolores (Evan Rachel Wood) simultaneously reaches her destination, the "city swallowed by sand," traveling through a different tense or two before coming face to face with Arnold. With multiple timeframes and extremely dense mythological developments in play, conveying the Arnold reveal in a way that makes sense and also ratchets up tension is no easy feat — which is why Westworld brought in the big gun, Michelle MacLaren, one of television's most prolific and accomplished directors, to helm the episode.

Read on for MacLaren's thoughts on the Arnold reveal, behind-the-scenes secrets of Maeve (Thandie Newton) and Hector's (Rodrigo Santoro) fiery hookup, the Man in Black's (Ed Harris) unfortunate encounter with a horse and a noose, William (Jimmi Simpson) rolling up his sleeves and stepping into the game, and more. First, we begin with what drew MacLaren into Westworld in the first place.

You've worked on a number of revered and popular dramas, from Breaking Bad to Game of Thrones and beyond. What appealed to you most about directing an episode of Westworld?

Westworld is unlike anything I've done. It's so deeply in the sci-fi world. X-Files, of course, touches on that world as well, but in a completely different way. For me, it was very much a departure from what I've done recently. That was a challenge, and exciting. It was fun to explore so deeply a different genre.

Did the Western notes of Breaking Bad prepare you at all for working within the world of Westworld?

Absolutely. I'm a huge Western fan. I'm a huge Sergio Leone fan. We did shoot Breaking Bad like a modern-day Western. Obviously Westworld is shot like a Western. Anytime I get to break out a 12 mil lens, I'm very excited. (Laughs.) I love the dramatic low angles. I love using a camera to really be able to express emotions and feelings and point of view, as we all do. With the Western, you get to do that in such an extreme way. When you're doing a Western genre like this, you can exaggerate it even more. I love that. It's really fun storytelling to me.

Westworld blends genres together. It has a science-fiction premise, but it's set within a Western world. What was the through line between these genres for you, as you worked on episode nine?

I think the most important thing is that the camera is always telling the story. You really rely on, and especially in this case, on the script, to keep the through line of the stories. We have to be aware of where all these characters are coming from and where they're going. You need to be very mindful of the previous episodes and their specific storylines and styles. It's important when you're up in the Mesa or in one of the Western towns to really lean into the Western style. When you're in the lab, if you think of it as more of a present day reality-based lab, then you will shoot it slightly differently than you would in a Western town. So we're always keeping in mind where you are and the story you're telling in choosing your angles and lenses to enhance that storytelling. That's how I maneuver through each of those genres, and thinking about what it is you want to say in this particular moment and how you hope people will feel.

Bernard was revealed as a host a few weeks ago. Your episode reveals that Bernard was modeled after Arnold. It's a big moment for the show's mythology. What were your initial thoughts when you read the reveal in the script?

I was really excited to find out that Bernard was Arnold. I had absolutely no idea. I thought it was so interesting that we got to see that he's a host yet again, too, and the psychological impact that it has on Bernard. Then it goes to a whole new level with finding out that he's Arnold. When you reveal something that's been really well laid out — there have been many Easter eggs leading up to this moment — so much of it is about him being revealed as a host that, at least for me, I didn't suspect that it went so much further, to discovering that he was Arnold, until you get to that point where you're closer and closer [to the reveal]. What I love about what the writers did is that they came at that reveal from several different points of view. They all had to come together in that ultimate moment when we reveal that Bernard is [based on] Arnold. I love that we get to see that from a number of different angles that meld together. I also think Jeffrey Wright did a wonderful job in that moment when he's Arnold, of being slightly different from Bernard. To me, that was very exciting. I loved shooting that scene, because we knew we were revealing such a big secret. And for Jeffrey, he was ostensibly playing a different character.

It's such a complicated reveal, because it's not just Bernard discovering that he's based on Arnold, but there's also Dolores traveling through at least two different versions of this town, and discovering Arnold as she descends deeper down the rabbit hole. Was it challenging to figure out how to bring this sequence to life, with these two intersecting narratives building toward the reveal?

It's challenging in that you're jumping through her memory and you're making those transitions, and you're trying to make sure people can follow and understand as she's realizing where she is, what's going on, who she is, and who can see what in that moment. There's a moment in the scene when a young Robert Ford walks past Dolores. He doesn't acknowledge her, because for him, she's not there. There are these little things that transpire that we needed to transitionally make sure people could follow along at any given moment. We used the wardrobe and the change in scenery and people in order to express that story. Also the lighting. [Cinematographer] Jeffrey Jur did a fantastic job transitionally, especially in the lab underground, to change the lighting as she was remembering things. A lot of this was done practically, when she's walking through the lab, and she transitions from the pant and shirt to the dress. That was all done practically. We used a piece of the set — a beam between the walls in the room on the set — and we had them take out a piece of the wall so the camera could dolly all the way down that hall. So those are just done through wipes in the wall as she transitions from one wardrobe to the other. If you notice, there's a hint on one end of the light. She sees the light start to change, and that's what starts her memory into that transition. It was all done practically.

You spoke before about the subtle differences between Jeffrey Wright's performances as Bernard and Arnold. What did you and Jeffrey discuss as you approached the scene where Bernard comes online for the very first time?

Jeffrey plays so many different levels in this episode. At that moment, there's a complete innocence in not knowing, an acceptance. He has no knowledge of anything we've just seen happen. He did a lovely job, even when he's looking at the glasses and putting them on. He's listening to Ford. He's doing what he's asked. It's all very positive and curious, like a young child in a way. I loved the simplicity with how he did that. There's none of the complicated history between him and Ford yet. He's very accepting.

Turning to a couple of the episode's other big moments, is there a behind-the-scenes story on the Man in Black getting caught in the horse-and-noose trap?

I will tell you this: Ed Harris did that all himself. (Laughs.) That man is incredible. We had a stuntman do one of the passes, and no offense to the stuntman, but we didn't need it. Ed did it all. Ed had a harness on and a rope around his neck, and had special effects and stunt guys doing the pull on him. But he physically dragged from the point where he took the knife out of Teddy, yanked back to that tree, at the speed that you're seeing, and hung up off of his feet. He did it himself several times. The man is incredible. He is badass. You look up cool in the dictionary, and it says Ed Harris.

What about the scene where Maeve and Hector have sex as their tent burns around them — how was that accomplished?

That was actually our last night of the shoot for the season! We shot part of it on location, and shot the burning part on the back lot of the studio out in Santa Clarita. We had half a tent, and we used long lenses. There were fire bars between the camera and Thandie, and when the fire was behind them, what we did was we put them at the open end of the tent, and the tent was treated with a special fire protection and a special glue that lights on fire, but is a controlled fire spread. We used long lenses to stack it up and make it look like they're much closer to the fire than they are, but they're always at a safe distance. When working with fire, there's always an element of danger. We had the fire department there and everybody was on standby. But Thandie and Rodrigo were never inside a close space with fire, but it looked like they were, by stacking up the lenses. It worked very well. When the camera was in the foreground, we had fire bars below the camera. What I was hoping was you would imagine the lantern, when she kicks it over, it races across the tent's back wall, shoots up, goes along the ceiling, down the walls, and consumes them all around. When she first kicks the lantern over, the blanketing and everything was treated so the fire shoots toward the camera, and when we turn around, it shoots up the back wall. All of that progression of fire is all controlled, and it's all real.

Then there's the scene where William breaks bad, if you'll forgive the pun. He kills all of Logan's (Ben Barnes) soldiers in the night, and while we don't see the act of violence, we see the carnage in the form of all these dead, dismembered hosts. What did you want to suggest about how the violence played offscreen?

The suggestion is that William snapped. He went crazy. He finally figured out, as he says, how to play this game. We do it all in one shot, starting on Logan, waking up the next morning. We don't know what happened. He'd been drinking all night, and he wakes up, and he grabs his crotch because he has to pee. To see this through his eyes, to understand the bizarreness of the moment and how unexpected and terrifying it is for him that such a strange violent act was carried out, and that it was William, really throws him off balance. This is not the William that we have known. He's finally said: "Enough is enough."

Everyone from Evan Rachel Wood to James Marsden has had a great Anthony Hopkins story to share. Do you have a memory from working with him on set?

Every moment working with Tony stands out. He's amazing. There were a few times I was so mesmerized by the performance that I forgot to say "cut." He's such a lovely, delightful man. He's very much a collaborator. When you give Anthony Hopkins a note and you get to discuss something and he walks away to give it a try, it's a really exciting and exhilarating feeling. It's an honor to direct him. At the end of our first day of shooting, my first assistant director turned to me and said: "I gotta go call my mom!" And I said: "Me too!" (Laughs.) It was a great honor.

What can you say about your next project, The Deuce, the new David Simon drama?

I just finished the season finale. It's fantastic. It's awesome. I did the pilot in the fall and just finished the season finale. It's amazing. Wonderful cast and fantastic scripts. I'm excited for everybody to see it, but extremely different from Westworld.

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