Best Performances: Westworld's Jimmi Simpson on William's Quick Devolution

Best Performances is TV Guide's Emmys video series highlighting the best acting performances of the year. Actors take viewers behind the scenes of their Emmy-nominated performances and explain the secrets of their craft.

One of the more emotional twists of Westworld's first season was the reveal that William (Jimmi Simpson) was actually the younger version of the mysterious Man in Black (Ed Harris). It was heartbreaking to realize that the man who fell in love with Delores (Evan Rachel Wood) during his first visit to the park would grow into the man who tortured her for his own amusement years later. William and Delores' relationship was so pure in those early days that many fans hoped to see that same dynamic continue into Season 2, you know, before William's full descent into his older alter ego. Unfortunately, it was revealed early on during the show's sophomore season that William became the Man in Black shortly after that first visit.

Emmys 2018: Ranking the Contenders for Main Title Design

For Simpson, this meant he was charged with showing the audience how the man he played in Season 1 could become the villain they loathed in Season 2. And he had just one episode -- Season 2, episode 2, "Reunion" -- to show the transition.

"[The episode] is sort of this amalgam of all this work that I had done in Season 1 combined with where this character is headed, defined by Ed Harris," Simpson tells TV Guide in our Best Performances video series. "I had all of these guideposts, yet all this freedom from my own performance. I felt so lucky to be the guy who bridges the gap between young William and [the] Man in Black."

That stroke of luck could actually turn into Emmys gold: Simpson is nominated for Best Guest Performance in a Drama for his performance in the episode. However, Simpson says he was actually taken aback by William's sudden transformation... at least until series co-creator Lisa Joy gave him a simple explanation for the accelerated evolution.

"I actually asked Lisa to meet me and explain the physics of this change, both narratively for them and character wise to me," Simpson reveals. "[She] explained to me, 'No, this is just a dude with a broken heart.'"

William's broken heart is on display for everyone to see in one pivotal scene featuring William and Delores in the Delos workshop. In contrast to Simpson's and Wood's scenes in Season 1, scenes in which they could actually interact, Simpson was challenged to show William's despair while Wood said nothing at all. She wasn't even allowed to move.

Emmys 2018: How to Watch This Year's Top Nominees

"There is so much non-verbal communication between William and Delores. It was difficult because our experience as of yet had been absolutely collaboration," Simpson says. "It was something I have never played before. It was wielding power with no reaction. It almost seemed like her inability to respond while we were filming it would cause him to feel the need to say even more."

The cruel dynamic was surprising, but Simpson was able to use the universal understanding of heartbreak to show how a naive and innocent William could become a man who tortures and kills for sport. In hindsight, it's almost too easy to see how he got there.

"To know he could break that quickly from Delores, I didn't expect it but I get it," he says. "I know so many men who, when they got their heartbroken, just instantly become an asshole to the person who broke their heart. It was just a sad and blisteringly truthful portrait of a man who hasn't gotten what he wanted."

The Emmys for guest performers will be handed out as part of the Creative Arts Emmys, which will be held over two nights, Saturday, Sept. 8 and Sunday, Sept. 9. The telecast will air on FXX Saturday, Sept. 15 at 8/7c.