In episode 4, Pluribus takes perhaps its most dramatic genre turn yet, strongly hinting that the Others’ hive-mind “Joining” is not a one-way street. It’s a reveal with seismic implications for the moral universe of the show, and it comes courtesy of Carol Sturka’s dogged if somewhat clinical query into what is true.
What Carol Discovers and How She Proves It
Carol (Rhea Seehorn) traps Larry (Jeff Hiller), one of the Joined who still holds the memories of Carol’s late partner, Helen. Her questions aren’t about geopolitics or alien strategy; they’re excruciatingly personal — whether you liked the book series, her unpublished novel’s quality, and what Helen really felt. The responses are painful, but they bear out one stark fact: The Others cannot create. They can hedge or dodge, but they don’t lie.
That constraint becomes a lever. When Carol finally confronts Zosia (Karolina Wydra), who has been hospitalized after the blast at the end of last week’s episode, she asks point-blank whether or not the Joining can be reversed. Zosia deflects. For Carol, that non-answer is a functional admission — silence as semaphore.
Carol then raises the stakes with sodium thiopental, the barbiturate long mythologized as “truth serum.” The drug reduces inhibitions; it doesn’t generate honesty ex nihilo. On herself, it lowers her defenses and reveals raw emotions, including a deep-dyed sense of ambivalence about Zosia. But when a dose is given to Zosia, the result is near-panic and an escalating distress response in the Others that leads to a medical emergency. The confession is louder than any message: there is something to be hidden, and that is reversibility.
The Truth Constraint: Raising the Stakes
Never mind the drama, that logic is intoxicating. Humans are notoriously terrible lie detectors: decades of research collated by the American Psychological Association find that average lie-detection ability hovers at about coin-flip levels, around 54%. The reverse of that baseline is the Others’ inability to lie. A refusal in interrogation theory can be as telling as an answer when one knows the rules of the subject. Carol knows the rules and then ruthlessly plays them.
This also resets the ethics of the season. If Joining is reversible, the victims are not lost; they’re potentially recoverable. The twist follows in the footsteps of earlier sci-fi pivots — Star Trek’s de-assimilated Borg, say — where an enemy collective is turned from an existential threat into a rescue mission. When the stakes transform from “How do we survive them?” to “How do we free them?”
Sodium Thiopental and the Myth of Truth Serum
Episode 4 flirts with an infamously contrived device. Sodium thiopental is an anesthetic agent based on barbiturates with rapid action. The American Society of Anesthesiologists details how such drugs depress the central nervous system, increasing suggestibility — a minor side effect hyped by pop culture as so-called “truth serum.” In practice, as studies cited by the American Psychological Association and such U.S. government research groups as the High-Value Detainee Interrogation Group have found, chemical disinhibition generates compliance and confabulation in equal measure to accuracy. It’s unreliable for veracity.
Which is why the episode’s cleverest beat isn’t the injection; it’s Carol reading how that reaction plays out.
Instead of a neatly wrapped revelation, she has physiological alarm calls and the desperate screams of networked Others, and evidence in negative space. The science deflates the serum mystique and the storytelling coerces enough of a conclusion to actually stick.
What a Reversible Joining Would Be Like for Everyone
Reversibility turns every tactical and moral question in the matter into a heap of ashes. If the Joined can be made whole again, hostage logic supplants wartime logic: extraction, rehabilitation, and consent are paramount. Real-world parallels do exist — including programs cataloged by the United Nations and independent research institutes on deradicalization and reintegration that emphasize long timelines, individualized care, the mitigation of harm. Translating that to Pluribus, any endeavor to un-Join people will demand surgical precision, not a blunt instrument.
It also rewrites Carol’s grief story arc, to do which with sufficient facility or grace would require a much longer leash. Her interrogation is a sign that she’s not just seeking intel; it’s the moment when we see that Carol is trying to prevent Helen from being fixed in loss. The avowal of an attraction to Zosia is not so much a love triangle as a character X-ray — Carol caught between memory, rage, and the person who represents both threat and potential remedy.
On a larger cognitive level, though, the show has been carefully laying down rules for the Others: unified memory and feeling, and now a tell that implies that the Joining is at least artificial rather than metaphysical. If it was engineered, it can be unengineered. That premise invites new story math — what a thing costs, who survives it, and which identities they wear in its aftermath.
Episode 4 does not deliver the “how,” but there’s no need for it to. By acknowledging the lock, Pluribus makes the rest of the season a quest to find a key that will unlock it and then close its lid — something that will test Carol’s courage, stretch out the Others’ appetites, and cheapen even further our commitment to certain rules about what counts as personhood on this show.
Pluribus is available to stream on Apple TV+.