This 'Westworld' actor figured out his character's twist based on nothing but his eyebrows

Warning: Spoilers ahead for “Westworld” season one.

Most of the “Westworld” cast was tasked with keeping major plot twists a secret, but perhaps the biggest one of all was the reveal that William and the Man in Black were the same person.

Though clues about this twist were dropped as early as episode two, the actor behind William — Jimmi Simpson — guessed the truth based on nothing but his eyebrows and a suspicious visit to the makeup department.

INSIDER spoke with Simpson after the season finale, and he told us the story of how he figured out William’s fate.

“Well that’s kind of a funny story,” Simpson told INSIDER. “Around episode three, I was asked to go to Christian — our makeup designer — so he could look at me. And he was staring at my eyebrows. He said ‘Would you mind if I changed your eyebrows?’ And I was like ‘no,’ but as a man no one’s ever asked me that question before and so I said, ‘What for?’ and he started just mumbling because he’s not an actor so he’s not ready to have a good excuse.”

“It was just weird that he didn’t give me an answer,” Simpson said. “I thought about it for a while and the only conclusion I could come to was that they were trying to make me look like someone else. When I thought about everyone else the only person I thought it could be was Mr. Harris.”

Until the final episode, Ed Harris’ character was only referred to as “The Man in Black.” This caused both viewers at home and the cast on set to constantly wonder what his real name would be.

Simpson took his hunch straight to one of the showrunners, Lisa Joy.

“And then I just happened to be walking to lunch and Lisa was like ‘Hey!’ and she started walking with me and I said, ‘Christian was just looking at my eyebrows’ and I then saw her face — it just tightened,” Simpson said. “And I said, ‘Am I … do I turn into Ed Harris?’ and she goes, ‘I can’t say anything. Don’t talk about that!’ and I go, ‘OK, ok, ok.’ So she kind of confirmed that for me.”

Even though Simpson knew William’s fate, he didn’t spill the beans to his fellow cast members.

“When [Lisa Joy] let me know that it’s not to be thought about or talked about, I just took it as law and I didn’t discuss it with anybody,” Simpson said. “That being said, Evan [Rachel Wood] was kind of the sharpest one of us for calling out what was going to happen. And she brought up that William might be the Man in Black I think around episode four. But then [she] instantly let it go because of the trajectory of William and Dolores. And I know part of it […] was just wishful thinking on her part, but I also dropped it into my very back pocket.”

Simpson was also careful not to let the knowledge affect his performance as William too soon.

“Yes, I paid attention to Ed’s stuff but I didn’t load the turn into William,” he said. “I just watched Ed more. And then towards the end of the season, around episode eight or nine, when William started being affected by these choices […] I started dropping in a little bit of Mr. Harris’ walk and tone.”

Even though Simpson figured out the truth early-on, apparently Harris was less keyed into the Man in Black’s history.

“I don’t know if I’m speaking out of turn but my impression and understanding is that Mr. Harris knew last — he was like the last person on set to be like, ‘Wait a minute, William’s me?'” Simpson said. “And I mean god d— he’s so brilliant. I rarely was on the same set as him and so when I was, I basically just quietly watched from behind other people. A couple times I said hello to him and explained to him what an icon he is to me, and then when he did find out we crossed paths and he stopped briefly and said, ‘You’re doing a good job’ and he winked at me and that was it.”

Read more from our talk with Simpson, including details on his on-set friendship with Evan Rachel Wood and another twist that truly shocked the cast.

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