Episode 3 of "A Murder at the End of the World" kicks off with a fleeting glimpse into the past. Darby and Bill are on their journey to the fateful location where Marissa Bahari lost her life. They deduce that the killer's arrogance led him to commit the crime in broad daylight, believing he would never be caught.
Returning to the present, Darby attends an evening gathering, where the atmosphere has calmed significantly since Bill's untimely death. Among the guests, only Darby and Lee harbor a genuine belief that Bill's demise was no accident. Ziba treats the assembled with a glass of shiraz, a prized Iranian wine, its aroma filling the air.
Darby's eyes land on Rohan amidst the crowd, but their conversation is abruptly cut short by Lee's intervention. Darby refrains from revealing what she saw in the footage and questions why Lee herself didn't hack into the feed. Their exchange is interrupted again by Ronson, who brings up their shared memories with Bill in Florida. Lee's nervousness is palpable, and she quickly steers the conversation towards Ziba's upcoming performance.
Darby attempts to interrogate Tomas, the waiter, about his visit to Room 11 on the fateful night. But he hesitates, his words trailing off. Sian, watching closely, warns Darby, "Do not bite the hand that might feed you," a subtle reminder of Ronson's influence.
Ziba's voice rises in song, a tribute to Bill, whom she admired and respected. As Darby listens, her mind wanders, hallucinating everyone wearing the mask, a testament to her suspicion that every individual in the room is a potential suspect. Snapping back to reality, Darby follows Tomas downstairs to the kitchen, where she eavesdrops on the staff being instructed to adopt a uniform response of "We can neither confirm nor deny" to any inquiries from journalists or diplomats. The tension mounts as Darby's investigation deepens, and the veil of secrecy surrounding Bill's death begins to lift.
Under immense pressure, Tomas confessed to Darby, revealing that he had carried three cups to Bill's chamber on that fateful night. Before departing, Darby hurriedly inscribed the names of the staff and guests etched on the wall onto her forearm, but curiously, Bill's name had vanished without a trace.
Returning to her chamber, Darby entrusted Ray with the task of scouring the internet for any conceivable connections between the guests and Bill. Their search yielded scant results, except for the mysterious absence of Rohan from any online records. It seemed he had gone off the grid in 2006, yet his emotional outburst at the gathering suggested a profound bond with Bill.
Through her window, Darby spied a figure venturing out onto the icy terrain. Curiosity piqued, she resolved to trail this individual. The figure revealed itself to be the killer, clad in a face mask and armed with an ice axe, their distinctive shoes adorned with red laces. Standing atop a small cliff, the killer signaled to someone in the distance, whispering, "One down...still a go." But before the recipient could respond, they apparently spied Darby and vanished into the shadows.
Darby returned to her chamber in a perilous state, her body temperature dangerously low. Ray swiftly intervened, helping her regain her composure. Just then, a knock sounded at her door. Darby jumped, but she opened it to find Lee, cradling Zoomer in her arms. The little one had been unable to sleep, and Lee gently placed him on Darby's sofa for the night.
Lee confessed to Darby how overwhelmed she had been with the event and caring for her son. Darby showed her the footage on the laptop, and Lee's expression turned grave as she beheld the mask. It was identified as an AI-evading mask, recently used by protesters in Hong Kong. Yet, this revelation failed to yield any further clues in their investigation.
Lee candidly reveals how Bill came to her rescue after she was drugged. Their bond, forged by mutual interests and shared concerns about the perils of technology, grew stronger. She confides that they did have a fleeting encounter, but it was an awkward experience for both. Lee offers to engage Darby's services to unravel the mystery of the killer, and Darby accepts.
The following morning, Darby and the others are invited by Ronson to embark on a journey to the South Summit, promising a glimpse into the future. As they ascend, Darby catches up with Rohan and inquiries about his connection to Bill. Rohan reveals that Bill was instrumental in his recovery, helping him overcome alcoholism.
Upon reaching the precipice, the guests are awestruck by the sight of a swarm of robots, working harmoniously to construct bridges and other structures. These marvels of engineering are the creations of Oliver, a pioneering roboticist, designed to alleviate the burden on humans in hostile environments.
After the excursion, as the guests return to change their footwear, Darby's gaze is fixed on the shoe rack. Her heart skips a beat when she spots Rohan picking up the shoes adorned with red laces. She repeats the phrase from earlier, and Rohan is startled. He sternly warns her to drop the matter, insisting that he would never harm Bill, though he doesn't deny being in his room.
Back in her room, Darby is presented with a cutting-edge helmet by Zoomer. This remarkable device transforms the surroundings into a vibrant, fictionalized world. Shortly after, Ronson arrives and escorts Darby away. He expresses his affinity with Walt Disney, comparing his creation of the helmet to the Disney legacy.
Then, he smoothly transitions into instructing Darby to depart. Ronson is aware that she has been grilling both the guests and the staff. He reveals a startling fact: the police didn't even interrogate Darby as they had extracted all the necessary information from Bill's blood. His heart rate had spiked significantly before Darby or the masked intruder's arrival, indicating that he had already administered the morphine.
Flashing back to the past, we witness Bill and Darby visiting Marta Diaz, one of the rare survivors of the serial killer's rampage. She bravely recounts her story of survival, handing them a silver pin that her sister had discovered in the car's trunk. They suspect it belonged to a previous victim. When Bill posts a picture of the pin online, he receives a response revealing its provenance. The pin turns out to be a class souvenir from Lincoln High School in Wickenberg, Utah, belonging to the Class of 2000.
Returning to the present, Darby decides to stay put. She heads to Rohan's room, but he remains silent behind the closed door. Unexpectedly, Todd runs into her in the hallway and asks her to gather her belongings. Darby shrewdly evades him, sneaking out through the back door with her laptop and a few essentials, feigning the need to pack. Just as she's making her escape, the phone rings — it's Rohan. He confesses that he visited the room and had feelings for her. He didn't want there to be any record of his visit, so he left when he sensed that Bill was in danger. Bill had uncovered a secret about someone but was unable to communicate it to him.
Suddenly, while still on the phone, Rohan is attacked, and the call is abruptly severed. Darby rushes to his room, but he's nowhere to be found. Screams emanating from the reception draw her and the other guests to the scene, where they find Rohan, lifeless. In a state of panic, Ronson orders Todd to usher everyone to safety, as another guest succumbs to the unknown danger.
