The Hollywood Reporter picks the occasional Man in Black's brain about why he wasn't always thrilled with his character's direction in the HBO drama: "I wasn't the happiest camper."

[This story contains spoilers for season three, episode six of HBO's Westworld, "Decoherence."]

What is the nature of the Man in Black's reality? It's a question at the heart of HBO's Westworld, and one for which Ed Harris' William does not have the clearest answer — a fact that frustrates the dark-hearted gunslinger, just as it does the man tasked with bringing the character to life.

In "Decoherence," season three's sixth installment, Harris' host-hunting antihero stands front and center — both for the audience, as well as for himself, as he embarks on a virtual therapy-induced internal battle against various versions of his own reflection: Jimmi Simpson's young William, an even younger version of the character played by Zayd Kiszonak, as well as returning James Delos actor Peter Mullan playing the role of the veritable group therapy leader. Along for the ride: three different "Men in Black," all played by Harris: William in a tuxedo, meant to embody the version of the man who presents himself to the world at large; William in Western attire, meant to embody the ruthless killer who stalked the park for so many years; and William now, all in white, a psychiatric patient forced to reckon with his own past.

How does William choose to reckon with it? The exact same way he usually does: with violence, and a whole lot of it. The Man in White kills all versions of himself, Man in Black included, and wakes up to Jeffrey Wright's Bernard and Luke Hemsworth's Stubbs standing overhead. The newly woke William returns to reality with an epiphany about himself: he's "the good guy."

What does that mean, exactly? The revelation will bear out in the episodes ahead, with some further light shed in the following conversation between The Hollywood Reporter and the man behind the Man in Black himself: Harris, speaking candidly about his frustrations over his character's arc in season three, and how he allowed his personal feelings to fuel his work as the character.

What kinds of conversations did you have with Jonathan Nolan and Lisa Joy about what was in store for the Man in Black this year?

I just was kind of curious as to what was going to happen and what was going on. And I really didn't get much input. It was pretty much revealed episode by episode what was going on with him, and I certainly didn't know how the season ended. I wish I had a better answer. First of all, I really enjoyed playing the Man in Black, right? Then all of the sudden, he's the Man in White. So I wasn't the happiest camper to tell you the truth, because I really enjoyed the part I was playing, and I was hoping that he, the Man in Black, would continue to somehow be prevalent in the story. And when I realized that was no longer the case, I had to just readjust my whole head and get into what was going on with William in this place that he has found himself, trapped in this facility, being tested, and whatever is going on with him.

You get to play the Man in Black again, but in this limited virtual reality capacity — as well as the "philanthropist" version of William, too.

Right. I'd had the experience of A, playing the corporate guy in his tuxedo in a number of scenes, where now he's the man. And obviously the Man in Black, I'd been used to playing him. Young William, obviously, I wasn't playing, and then there's [the Man in White], who is under the control of the facility. The costume [helped]. Once you put the tuxedo on, you're that guy. Once you have your Man in Black suit, you're that guy. When you're the guy in the white, then you're in a whole other situation. You're shooting one of these guys at a time, and you're just focused on that particular aspect of his character. So I mean, it took a little while and a lot of costume changes...but it was pretty interesting, I got to say.

What did you discover about William, as you started digging into this new take on the character?

I mean, he's been so deprived of any sense of freedom that I think he's really just trying to survive. I mean, when they put that...whatever it is they do, put him in a straight jacket, they strap him in his chair, I mean, what choice does he have other than to let him stay in place? And once they do, he's trying to evaluate what the hell is going on with him and who's doing what to who, etcetera, and who's in control, and what's happening at Delos, and all that kind of thing. And so, it's just a lot of questions that he has more than anything. You know? His state of mind is like...he's all over the place. He's going crazy. He's wondering if he's still who he is. He doesn't know if he's a host or not. He's totally at the whim of the powers that be at the moment.

It's jarring to see him so powerless. Not that he wasn't powerless at points in season two, but this is a different level. It must have been jarring to play, too.

Yeah, it was. It was jarring. To tell you the truth, it was hard to enjoy.

I'm sure.

In other words, I didn't like it. I still don't. But that's my problem.

What you're going through as an actor playing the character, it's emotionally similar to what's happening with the character.

Definitely. I definitely allowed my own feelings about it to influence what I was doing. (Laughs.) I mean, I still enjoyed working on it! I still enjoyed working on the show. It was just a whole different way of enjoying it, you know? I got to say, it was a little bit aggravating.

What do you think it means when William says he's "the good guy" now?

I think what he means and what he's feeling is, if he ever gets out of here, if he ever can assume control of his own destiny on some level, then what he's after is to rectify this whole situation. In other words, he understands what has happened, and he faults himself for most of it. I mean, it's his fault, this whole world that he helped create is now blown up, and who knows where it's going? He's not sure quite what's happening outside in the world, but I think he feels determined and has set his mind on trying to do some justice here. In that sense, I think he feels he's the good guy.

This interview has been edited and condensed for clarity.

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