What Just Happened to [Spoiler] on ‘Westworld’? A Refresher on ‘Fidelity’

[WARNING: The following contains MAJOR spoilers for Westworld Season 4, Episode 4, “Generation Loss.”]

Well, looks like The Man in Black (Ed Harris) and James Delos (Peter Mullan) aren’t the only Westworld characters answering questions for an ominous baseline interview. Caleb Nichols (Aaron Paul) is “in the thing” now, too.

After dying at the Delos construction site 23 years ago, Hale-ores (Tessa Thompson) recreated him hundreds of times as part of a mysterious experiment, testing the host version of him for fidelity. But what is “fidelity,” and where have we seen it on the show before? Here’s what you need to remember about hosts with human consciousnesses and the tests they undergo.

The First Experiments Were in Season 2

The first human to submit to fidelity testing was James Delos, the founder of the Delos Corporation. As we learned in “Riddle of the Sphinx,” human Delos died of an incurable disease… but not before having a pivotal conversation with young William (Jimmi Simpson), referred to as a “baseline interview.” The goal, as the episode states, is that the host version of Delos would replicate that initial conversation with the human Delos exactly, proving that he’s a completely faithful replication of the human whose consciousness was transferred into a host pearl. The end goal? Immortality, in an indestructible host body.

Unfortunately, that’s not how things worked out for Delos Sr. Throughout the episode, we see William come to visit him and attempt to have that same conversation, only for Delos to break down or malfunction in the process. (Granted, some of those glitches were definitely William’s fault; in the last one, he tells host-Delos that his son died of an overdose and his daughter committed suicide. Human or host, that’s bound to cause some glitches.) The initial experiments lasted decades, and Delos himself was replicated 149 times. None of those attempts achieved true fidelity, and the final Delos copy was left in his incineration chamber to slowly go mad. Lovely.

HBO

William Also Underwent Fidelity Testing

William’s experience with fidelity testing, as with many things in Westworld, was less than straightforward. In Season 2’s post-credits scene, we saw a host version of William’s daughter lead him into a similar chamber to the one where Delos was housed. There, she tells him she’s going to ask him some questions. Why? “Fidelity.”

We know this takes place in the future relative to Season 2’s timeline, and it’s possible that this version of the MIB did achieve fidelity. But we don’t know who was testing him, or why, or where this takes place in the timeline. Interestingly, there’s sand in the room he and Emily (Katja Herbers) walked through, which might indicate he’s not all that far from Bernard’s timeline.

What Does It All Mean for Caleb?

Hale-ores wasn’t wrong: fidelity testing was started by Caleb’s “kind.” But what makes Caleb different is that he’s a human transferred to a host body created by hosts, rather than a human transferred to a host body created by humans, like Delos. With that said, it doesn’t seem that made for a smooth transition from humanoid to android — Hale-ores says she’s on the 278th version of him. As he remembers what actually happened to him on the night he and Maeve (Thandiwe Newton) tried to escape the park, Caleb starts to glitch as Delos did; he twitches uncontrollably and spasms, and he has trouble speaking. Maybe Caleb-278 wasn’t quite it, either.

But there are some differences in the way Hale-ores is conducting her test. For one thing, she doesn’t appear to have a questionnaire for Caleb the way William did for Delos; for another, she’s certainly not a “trusted person” of Caleb’s to administer it. It’s possible they’re running host-Caleb through a simulation of his last days as a human to determine if he consistently reacts the same as his human self without breaking down, thus achieving fidelity. As for why? Hale-ores went out of her way to trap and infect Caleb with the parasite in ‘20s-World, so clearly, she needs him for something. (But she must not have needed him as a human, otherwise… why would her soldiers have killed him?) He was the last person with control over Rehoboam, which could be significant. But as for whether or not he achieves true fidelity, we’ll have to wait and see.

Westworld Season 4, Sundays, 9/8c, HBO