WARNING: The following contains spoilers for Season 3, Episode 4, of Westworld, "The Mother of Exiles," which aired Sunday on HBO.
As Westworld's third season reaches its halfway point and many of the key players begin to meet up, viewers are slowly learning more about the new characters and the world they inhabit. "The Mother of Exiles" offered up a little more information on this season's main villain, Engerraund Serac. Serac wants Delos' data as well as Dolores Abernathy taken care of, but his motivation wasn't clear until "The Mother of Exiles," and it ties all the way back to Season 2.
When Serac and Maeve Millay are sitting down at a restaurant in Singapore, Serac talks more about his past growing up watching Paris get destroyed by a nuclear bomb, which ultimately led to Serac gaining control of Rehoboam, an AI unit that collects data on human beings so it can correctly predict they best possible outcome for their future. Living in a world controlled entirely by advanced technology, this allows Rehoboam to manipulate the outcomes of people's lives so the worst kind of people can't diverge from their paths and create chaos on the same level as the event in Paris.
Though Rehoboam's data is vast, Serac believes it is incomplete. He then recruits Maeve to kill Dolores so he can acquire the data he wants: the secret project in Sector 16. If Maeve does this, Serac will reunite her with her daughter in The Valley Beyond. The secret project Serac keeps referring to is actually The Valley Beyond itself, though it was previously referred to as The Forge before the events of the Season 2, Episode 10, "The Passenger."
The Forge was created by Delos Inc., the company financing the park. The Forge was a massive storage unit that housed the data of all the guests that entered the park. Though it was billed as a way to better understand their clients, Delos' true intentions were to use the guests' data to perfect human code and copy human consciousness into hosts so humans could potentially live forever. The project was eventually deemed a failure when several host versions of founder James Delos failed to read the code properly due to a lack of understanding of human decision making. It was eventually revealed Bernard Lowe reprogrammed the Forge to allow Dolores total access to better understand how humans work.
Unbeknownst to Delos, Westworld's former director Robert Ford had used The Forge's servers to house his own secret project, The Valley Beyond. Accessed through a "Door" only the hosts can see, The Valley Beyond allows the hosts' consciousness to leave their bodies upon entry so their minds can live on in a "virtual Eden" that cannot be accessed by humans. During last season's finale, Dolores purges The Forge of the guest data and flooded the Sector and the valley, but not before moving The Valley Beyond to a secret location via satellite so the hosts who escaped cannot be found.
The Forge was revisited briefly back in Season 3, Episode 2, "The Winter Line," with Maeve walking through a simulated version of it conjured by Serac to see if she has any information on the real Forge. Though it does not exist anymore due to the flooding, The Forge/Valley Beyond looks to play a big role in the season going forward. Delos' goal of immortality was never fully realized, but Serac's plans for a controlled future where everyone follows their predetermined loops could become a reality.
Airing Sundays at 9 p.m. ET/PT on HBO, Westworld stars returning cast members Evan Rachel Wood, Thandie Newton, Ed Harris, Jeffrey Wright, Tessa Thompson, Luke Hemsworth, Simon Quarterman and Rodrigo Santoro, joined by series newcomers Aaron Paul, Vincent Cassel, Lena Waithe, Scott Mescudi, Marshawn Lynch, John Gallagher Jr., Michael Ealy and Tommy Flanagan.