Caleb and Maeve explore Temperance, the new Prohibition-era theme Delos park, and exploit the carnage of the staged robbery at the local saloon to sneak into the underground to find out what William's plan is. However, to their horror, they find the underground area to be another level of the game: A hidden realm where park guests can reenact the host rebellion. Eventually, they find the real basement level where they discover Drone Hosts creating flies that would be used to control the humans via a mysterious audio signal only hosts can hear. From there, they see the human subjects being forced to commit suicide. Caleb sees his daughter Frankie as one of the prisoners but before Maeve realizes that she's a host, Caleb is locked in the prison cell with his "daughter", who turned out to be a host, and unleashes a horde of flies upon Caleb. Maeve tries to save Caleb but is stopped by the Man In Black host.
Meanwhile, a host version of Caleb's friend Carver kills the real Carver to capture the real Frankie and her mother. But Frankie discovers the body of the real Carver and alerts her mom, who shoot the host Carver as the two then flee from their home.
Finally, at some unknown point in the future, Bernard awakens from the Sublime after discovering some shocking truths from Akecheta. Akecheta reveals that the Sublime consists of countless pocket universes, giving any host who made it to the Sublime their own "perfect world". After explaining that one year in the real world is a thousand years in the Sublime, various hosts used their "pocket realities" to explore what would happen in the real world before realizing that Earth and humanity were doomed due to an incoming apocalyptic level event. Akecheta shows Bernard how he can bend reality in the Sublime to chart any possibilities to find out how to stop the apocalypse. Waking in the real world with a newfound able ability to "predict the future" due to his countless simulations, Bernard and Stubbs head to a local diner where Bernard kills and decapitates a pair of men who turn out to be hosts that were set to meet with a high ranking contact in a human resistance group. The contact is initially suspicious of the two until she brings them to her group where Bernard reveals he knows where to find the weapon that they're looking for.
Tropes:
- After-Action Patch-Up: After a shootout, Caleb and Maeve have an intimate scene where he treats her wounds.
- Anachronism Stew: A piano cover of "Bad Guy" by Billie Eilish and "Enter Sandman" by Metallica are playing in the bar in Temperance, with the latter replacing "Paint It Black" during the heist sequence in the new park.
- Aspect Ratio Switch: The aspect ratio changes to anamorphic widescreen for scenes of Bernard in the Sublime.
- Bait-and-Switch: It appears Frankie has been kidnapped by Hale, but in fact she's just a host copy Hale made because her attempt to kidnap the real deal was foiled.
- Big Good: Akecheta fulfills this role again, declining to return to reality to help save reality, but giving Bernard the (virtual) time he needs to calculate how he can do the job himself.
- Blindfolded Trip: The resistance group hides out in the desert so Bernard and Stubbs have to wear blindfolds when being taken to them.
- The Bus Came Back: Akecheta returns in this episode to help Bernard find a way to save the world.
- Call-Back: The heist sequence in the new park is a modern rehash of the heist scene in Westworld. Maeve is not impressed by Hector's cheap knockoff.
- Can't Kill You, Still Need You: Bernard barters his way into the resistance by offering knowledge of the location of the weapon they seek. That he knows their objective and where they were looking is sufficient to keep him alive, even though they're equally suspicious of the fact that some random dude has detailed knowledge of their operations.
- Chekhov's Gun: Caleb keeps a gun in a safe which Uwade uses eventually to kill the host copy of Carver.
- Chekhov's Skill: In the first episode, Caleb teaches Frankie how to aim and shoot properly with her BB gun. Here, Frankie seems to have mastered it by shooting the host copy of Carver in the eye with her BB gun.
- Cliffhanger: The episode ends with the Frankie host infecting Caleb with flies, while Maeve is facing the Host-duplicate of William.
- Combat Clairvoyance: Bernard's knowledge of the future allows him to easily beat down two guys at the diner, knowing in advance exactly how they'll react.
- Decapitation Presentation: Bernard presents the head of a man he's scalped, thereby revealing the Cranial Processing Unit within, to demonstrate that he protected the resistance from being infiltrated by hosts.
- Decoy Hiding Place: Carver suspects Frankie to be hiding under her bed. He is surprised when he doesn't find her there.
- Desert Punk: The scenes with the resistance group and their futuristic vehicles and weaponry in a desert environment.
- Expy: The knock-off Hector and Armistice in "Mafiaworld" bring to mind the film versions of Bonnie and Clyde. The latter even sports a Faye Dunaway-esque beret.
- Extremely Dusty Home: The motel room Bernard has been staying in for years while visiting the Sublime has become extremely dusty.
- Foreshadowing:
- When Bernard wakes up, it's shown that a very large tree has grown outside the now-abandoned motel, its size suggesting his trip in the Sublime may have been longer than the previously-established seven years between the end of season 3 and the present day.
- For that matter, the resistance seems awfully well-established for a threat that, aside from knocking off some politicians, doesn't seem to be actively menacing humanity just yet, plans to do so notwithstanding.
- Hell Is That Noise: The tones produced by Hale's Mind-Control Device sound like the ominous droning of an untuned pipe organ... to hosts. To humans, the tones are below normal hearing range and come across as a rough stuttering from speakers.
- Internal Reveal: Maeve learns that William is now a host.
- Kill and Replace: Carver, one of Caleb's military buddies assigned to protect his family, was killed by his host copy as Frankie finds out.
- Literal-Minded: Bernard is slightly annoyed that Stubbs took his directive to not disturb anything while he was in the Sublime as license to let him literally gather dust in the hotel room.
- Lured into a Trap: Caleb and Maeve infiltrating Temperance and the underground facilities where they discover the flies and the human test subjects is in fact a trap designed by Host-Charlotte to capture Caleb. She even uses a host copy of his daughter to trick him into thinking that Frankie is kidnapped.
- Mama Bear: Uwade grabs a gun and shoots Host Carver in the head when he threatens her daughter.
- Mexican Standoff: Ensues between Bernard, Stubbs and the female resistance fighter in the car. The tension gets resolved when Bernard orders Stubbs to hand over his weapon.
- Not in This for Your Revolution: Akecheta declines Bernard's invitation to go back to the real world to save it, being content with the worlds he's built in the Sublime.
- Oh, Crap!: Maeve gets two such moments in quick succession, when she realizes Caleb has been lured into a trap with a replicant of his daughter, and moments later when she confronts the Man in Black and realizes he's been replaced by a host version.
- Papa Wolf: When Caleb and Maeve see Frankie among the test subjects, Caleb does everything he can to reach her. Unfortunately, this leads to his downfall when he realizes "Frankie" is a host, which then infects him with the flies.
- Personalized Afterlife: Each mind in the Sublime constructs its own world, and as such they are largely separate from one another. As Akecheta notes to Bernard, the world they're in is of Bernard's design, and he's the only person who cared to visit.
- Plagiarism in Fiction: Many parts of the new park are rehashes of narratives from Westworld and Shogun World. Maeve warns Caleb not to trigger the Dolores narrative by picking up a can of food from the street. There's a sleeping drunk man teased by children, law enforcement trying to recruit men to hunt down Hector, the local bar/brothel is almost identical to Maeve's old saloon. To Maeve's annoyance, the bar is hit by gangsters in a complete copy of the theft sequences from Westworld and Shogun World, right down to the dialogue.
- Reclaimed by Nature: The hotel Bernard has been staying at has since been abandoned and nature has taken its course, including a tree having grown right through the walkway just outside his room.
- The Reveal: The flies don't just drive humans crazy, they render them susceptible to low-frequency sounds that can control their behavior. As Hale indicated previously, she doesn't just want her hosts to replace humanity, she wants to make humans the hosts in her new world.
- Seamless Scenery: While in the Sublime, Bernard transitions from the Ghost Town location to a contemporary city environment just by passing along a column.
- Soundtrack Dissonance: Blondie's energetic "Call Me" plays over the dramatic scene of Bernard curbstomping two guys in front of the diner.
- Spotting the Thread: Frankie notices something odd about Carver when he doesn't seem to remember the promise about teaching her teddy bear some fighting moves and returns her teddy bear to her with a bloodstain on it. Her suspicions are confirmed when she sees a Trail of Blood outside the house and finds the real Carver dead.
- Warm Place, Warm Lighting: Scenes in the desert have an orange filter applied.
- War Reenactors: The hidden Easter Egg of Temperance is a recreation of Westworld's host rebellion, complete with a recreation of the underground facilities used to condition hosts. It takes Maeve a bit to realize it's actually part of the game, with hosts playing the part of Quality Assurance guards, while the real facility is one level below it.
- Year Inside, Hour Outside: A millennium inside the Sublime is equal to a single year in real time. This has allowed the hosts to calculate thousands of possible timelines, allowing Bernard to figure out a timeline where things don't end in total disaster.
