Pluribus season 1 episode 4 ending explained: Did the truth serum work on Zosia?

The world of Pluribus season 1 continues to grow darker and more psychologically complex as the Apple TV+ sci-fi drama pushes its characters into increasingly desperate situations. Created by Vince Gilligan and led by Rhea Seehorn, the series examines a near-future reality where humanity has been consumed by a euphoric alien hivemind, leaving only a few immune survivors struggling to retain their individuality.

Episode 4, titled Please, Carol, pushes Carol further into investigative mode as she tries to determine whether the hiveminds truly cannot lie, and whether that limitation can finally give her access to the answers the hive has been keeping from her.

Carol’s risky decision and its deadly consequences for Zosia

The unraveling of Episode 4 hinges entirely on Carol’s desire to learn how to reverse the Joining. Her breakthrough comes when she confirms through Larry that they are incapable of lying. After witnessing how direct questioning still results in evasive silences from Zosia, Carol comes up with the thought of checking the effects of truth serum, to force required information from her regarding how to reverse the joining. 

Carol steals sodium thiopental from the hospital pharmacy. She first injects herself with a small dose, hoping to understand what the drug actually does. The result is a deeply humiliating recording of her confessing her pain, grief, anger, and conflicted feelings about Zosia. Even so, the experiment convinces her that the serum loosens the mind’s defenses, and that it may work on someone connected to the hivemind.

Her next move is far riskier. Under the guise of taking Zosia outside for air, Carol quietly injects the drug into her IV line. As expected, Zosia’s speech slows, her focus blurs, and her connection to the collective appears weakened. Carol immediately begins hammering her with the same desperate question:

“How do I reverse the Joining?”

From this point forward, the scene becomes unbearably tense. The Joined begin gathering around them, forming a circle. Their eyes fill with tears, they whisper together the same phrase: 

“Please, Carol!” 

Contrary to Carol’s fear, they are not trying to stop her or punish her; they are experiencing Zosia’s pain and pleading for Carol to let her rest.

But Carol is terrified of losing her only chance for answers. Out of fear that the hiveminds will take Zosia away, she uses handcuffs and locks herself to Zosia’s wrist. It is a final, symbolic act of claiming agency while simultaneously stripping it from someone else.

The drug then hits Zosia far harder than Carol anticipated. Her body collapses under the combined strain of sedation, distress, and her existing injuries. She slumps to the ground, gasping, before going completely limp as her heart stops. Only then does Carol step aside, allowing the others to begin CPR. The episode cuts to black without revealing whether Zosia survives, leaving the aftermath of Carol’s actions suspended in uncertainty.

Recap of Pluribus Season 1 Episode 4

Episode 4 opens with Manousos Oviedo, an immune survivor living in a storage unit. His introduction offers a glimpse at how other individuals outside the hive navigate isolation, rationing, and fear while trying to gather information about the world’s changes.

Carol’s storyline begins with her documenting everything she has learned so far about the Joining. Her notes help her confirm that the hive mind appears incapable of lying, but she wants verification. She asks Larry a series of direct questions, including personal ones about her own books, and the blunt honesty she receives reinforces her belief.

Later, Carol visits Zosia in the hospital following the previous episode’s explosion incident. Their conversation confirms that the hive knows more about the Joining now than when it first began and that Zosia cannot explain reversal methods even if they exist. The tension in the scene convinces Carol she must take action if she wants definitive answers.

Carol steals sodium thiopental from the hospital pharmacy. In her apartment, she injects herself with a small amount to determine whether it forces unfiltered honesty. Reviewing the recording afterward, she sees that the drug works as intended and that she reveals personal truths she typically avoids acknowledging.

She returns to the hospital and brings Zosia outside for fresh air. In a quiet moment, Carol uses the sedative on her and begins pressing for information. Zosia struggles to stay conscious, and the hive members gather as they sense her distress. When Zosia collapses, the hive moves in to help, while Carol watches the situation unfold without receiving the answers she hoped for.

The next episode of Pluribus season 1, titled Got Milk, will be released on November 26, 2025, exclusively on Apple TV.