'Westworld' actor on filming season one and the plot twist that shocked the entire cast

HBO

Warning: Spoilers ahead for the "Westworld" season finale.

"Westworld" concluded its premiere season with a jam-packed finale episode. One of the biggest confirmations was the revelation that William and the Man in Black were the same character whose scenes were taking place 30 years apart. 

INSIDER caught up with Jimmi Simpson (William) after the finale to talk all things "Westworld" and his experience filming the first season.

"I don't think I've ever worked on such an expansive set when you're talking about just geography, the caliber of actors and the number of actors, the number of writers and producers and the epic sized crew," Simpson said. "But despite all of that it considerably felt like a small family. So 'camaraderie' doesn't even do it justice because it's not just like a couple of the actors got along and played Dubsmash - everybody hung out all the time and we just really loved each other very much."

Simpson and his co-star Evan Rachel Wood (Dolores) have been sharing their Dubsmash videos  - short voiceover clips featuring iconic movies or songs - on Twitter throughout the last few months. 

[Warning: NSFW language in the following clip]:

"Most of those Dubsmashes are Evan and myself, and they were really just like a spit valve effect we had after having to throw ourselves into such deep emotional turmoil for such long nights towards the end of the season," Simpson said. "Both Evan and I are very emotional actors and we do our best work when we're allowed to really live in that space. So we both spent all those days in a very sad and tense emotional state, and at the end of the night we just said 'hey you wanna smash?'/'yeah let's do it' and that's how we'd just shake it off."

John P. Johnson/HBO

Though it was a grueling experience, Simpson says that the days spent filming on location in desert areas were some of the most memorable.

"The entire ten days Evan and I spent in the desert working we did a majority of our stuff there getting those natural backgrounds and running from scene to scene," Simpson said. "We had nothing but each other to keep from going crazy. It was ten days of the hardest work I've ever done, and most of the emotional stuff was strenuous acting work but it also created a relationship with Evan that will probably last a lifetime so that was the best time."

HBO

Part of the shared experience on set for the cast was theorizing and trying to guess what would come next, since they all (for the most part) received just one episode script at a time. So when the show was finally airing on HBO, Simpson and his fellow castmates closely tracked the fandom's theories.

"I was really surprised after episode two when people were calling out s---, like specific s--- that you weren't supposed to even think about for four more episodes," Simpson said.

We asked if he or the group at large had any theories of their own that wound up being totally off the mark.

"I think because we had the text we could read it unadorned by the spectacle of the actual show, we maybe had a slightly clearer idea of what wasn't happening," Simpson said. "But man, like the Bernard thing f----ing shocked us all. We all ran over to him like 'How long did you know?!' I thought [that twist] was gorgeous. Oh god, beautiful. And Jeffrey Wright's execution was such a large part of that beautiful deception."

John P. Johnson/HBO

Since William never crossed paths with several of the other characters, Simpson followed their stories closely while watching the finished episodes.

"The people I didn't interact with very much that I'm most intrigued by are Jeffrey [Wright] and Thandie [Newton]," he said. "Those two characters are so immensely interesting to me and gosh I don't think those two actors could be any better than they are. So yeah I'm tuning in for them and then, of course, Dolores is my favorite."

Some of Simpson's favorite non-William scenes were the ones filmed with just Evan Rachel Wood (Dolores) and Jeffrey Wright (Bernard/Arnold).

"There are a couple scenes in [episodes] two and three when Bernard/Arnold and Dolores are talking and they're so subtle and it's just discussion from two seated actors but I don't think there's anything more compelling than what those two are doing in those scenes," Simpson said. "Jeffrey's artistry in interacting with this host and Evan's ability to change from an emotionally connected human to a computer ... I think that should not just win an award - it should start its own award from here on out."

HBO

"Westworld" has a pretty killer cast - a fact that didn't go unnoticed by Simpson. "It's blinding somtimes," he said. "I mean you put Anthony Hopkins on a show and I guarantee you every actor there will be doing their finest work."

Not only was the acting through season one applauded by critics, but the show's writing treatment of female characters was also noted. Between Dolores and Maeve, the two main hosts we followed, there was plenty of subversion when it came to standards for women on screen.

"Thandie I didn't work with but we got along like a house on fire because she is who she appears to be - such an excited and invested actor getting this role and just killing it every day," Simpson said. "And it was the same with Evan. She's an actress who's been in the spotlight for her whole life and has had the ups and downs we all have and then to see her rise to this occasion ... Both of them are just redefining performance in a way. It was just inspirational."

John P. Johnson/HBO

"And it comes from the top, too," Simpson said. "You have Lisa Joy and [Jonathan Nolan] creating this whole scenario, choosing every element, creating it from ground up, and they are just model humans. Lisa is an insanely smart and emotionally generous woman and [Jonathan] is the same. It doesn't feel like 'men and women' it just feels like we're all together and trying to make things even - like they should be - as opposed to 'Oh this is the woman's job.'"

Simpson recognizes the powerful way in which the women hosts dominated the most important narratives.

"Literally it's their show - it's Dolores' show," he said. "It just felt like the way things should be and we weren't fighting any prior bulls--- even though it's there, this show just lived by itself in a bubble where women were as important as men. Can you believe it?!"

John P. Johnson/HBO

"[The women] are elevated in such a way that's not like the typical 'Hey let's elevate these women so they're more like this man and look at how they're doing these man things only men get to do,'" Simpson said. "They show you the power of femininity in a way that no male actor could even try to execute. [Lisa and Jonathan] both understand the power of emotion and that's generally considered like a 'feminine' quality, but here we just understand that, well, f--- whether it's men or women - it's powerful and it's what runs us all, so you're going to have to bow down to it at some point."

John P. Johnson/HBO

As for his role in the first season of "Westworld," Simpson says he's grateful for the fans who are loving the show just as much as he did while creating it.

"I really did feel like the small time little league guy who got invited to play with the big guys," he said. "And I feel real happy with the work and I feel the same way [the fans] do. It's such a great show."

To learn more about Simpson's thoughts on William's major finale twist and what he knows about season two so far, read more from our interview with the "Westworld" star.