Episode 3 of Season 1 of "The Eternaut" kicks off with a nostalgic flashback to the fateful night of the snowstorm, delving into Inga's poignant backstory. She valiantly took on her brother's responsibility, opting to make a crucial delivery for him so he could complete his football game.
Elsewhere, Tano furiously attempts to establish communication with anyone via the radio, to no avail. Lucas, growing restless, suggests they venture out in search of assistance. Amidst varying opinions, Lucas's insistence that they abandon the town rings loud and clear. However, Tano firmly declines, digging his heels in. Juan, driven by concern, borrows the car with the intention of finding Clara, only to be met with Tano's unwavering refusal. Tano emphasizes the importance of staying united.
Their neighbor Benito then steps in, pleading with Tano to lend him the car for a vital supply run. Despite Benito's earnest plea, Tano refuses, sparking a heated debate. In the midst of their altercation, Omar seizes the opportunity, stealing the car and speeding off. Benito departs, leaving Tano fuming over his alliance with Roberto, a man with whom he had a bitter falling out two decades ago.
Omar's journey takes a dramatic turn when he encounters a colossal wreckage blocking the road. In a desperate maneuver to avoid it, he swerves, ultimately resulting in a harrowing accident. Just as consciousness slips away, he catches a glimpse of a mysterious red light piercing the sky.
Fortunately, Omar is eventually discovered and rescued by an unseen Good Samaritan.
Meanwhile, Elena and Juan embark on their own quest, setting out to find a vehicle to reach Clara's school. Their night takes a harrowing turn as they're forced to hide in a car from marauding looters, Elena's worries about Juan's fragile mental state intensifying. Ever since his return from the military, Juan has been avoiding the use of firearms, a stark contrast to his past.
Back at Tano's house, tension mounts as the sounds of looters echo outside. Tano spends a sleepless night, repeatedly trying and failing to establish radio contact.
As dawn breaks, Juan and Elena finally arrive at the school. To maximize their search efforts, they decide to split up. Juan sets off to locate a functional vehicle, while Elena stays put to track down Clara's friend's address, the weight of the unknown pressing heavily on her shoulders.
As she delves into the office, a sudden noise catches her attention, prompting her to investigate further. To her astonishment, she discovers a young boy, Pablo, confined within a closet. It transpires that his friends had intended to play a prank on him, but fate intervened, claiming the lives of all involved. Meanwhile, Juan returns with a car, eager to warn Pablo about the perilous snowfall. However, the young man's brash demeanor renders him indifferent to Juan's urgent warnings. The grim reality dawns upon Pablo only when he beholds the lifeless bodies of his friends outside the school. Reluctantly, he agrees to assist Juan and Elena, on the condition that they escort him home afterward, with the added mission of finding Clara.
Tragically, Pablo betrays their trust by providing a false address. Upon arriving at his house, they encounter a scene of devastation, with every inhabitant lying lifeless. The sight of death strikes Pablo deeply, leaving him with a feverish condition. Seeing his plight, Elena persuades Juan to break into a nearby pharmacy to procure medication for the boy.
Inside the pharmacy, a young woman unexpectedly emerges, pleading for their assistance with a fake pretense of impending childbirth. Despite Juan's misgivings, Elena allows her in, unwittingly falling into a trap. The woman's real intent was to distract them, buying time for her boyfriend to launch a surprise attack. The couple seizes Elena's bag and confines her and Juan in a toilet, overlooking the presence of Pablo, who remains hidden.
Once the couple departs, Elena manages to convince Pablo to release them. As a gesture of goodwill, they give him the mask they had been saving for Clara, and together, they set off towards Tano's house. Throughout this tumultuous journey, Juan continues to be haunted by visions of a crimson sky and a mysterious figure.
Along their journey, they encounter a family packing their belongings into a car, preparing to flee the town. Once more, Elena steps in, pleading with Juan to let them be on their way. Meanwhile, Inga returns to the park in search of her brother, only to discover his lifeless body. Devastated, she makes her way back to Tano’s house, where she finds solace in the comforting embrace of Elena and Ana. Tano, determined to keep their spirits high, urges them to focus on their survival rather than dwell on their loss.
Placing his trust in Inga, Tano hands her a gun and assigns her the duty of guarding their safe haven while he ventures out to gather more supplies. Lucas joins him in this endeavor, and together they head back to the fire station. There, they come across Benito and his team. Benito, intent on sealing off all the roads, also presses Tano to reconsider his earlier decision to welcome them into his garage. He gives Tano a ultimatum of 24 hours to reconsider his stance. Tano is disgruntled, particularly by the notion of isolating themselves further by closing the roads.
Returning home, Tano establishes contact with a man from Uruguay, who reveals that he too has been in communication with someone in Brazil. They all share a common plight: the deadly snowfall that has blanketed their world. From their conversations, they deduce that this catastrophe is a global phenomenon.
Regrettably, their conversation with their newfound ally is cut short. Desperate to reestablish contact with the Brazilian, Tano attempts to adjust his aerial. It is during this endeavor that he notices something amiss with his compass.
After a arduous trek, Juan, Elena, and Pablo finally arrive at Tano’s house. This time, Tano is resolute in his decision to abandon the town and seek refuge in his other home on the island. He has also come to the realization that the Earth’s magnetic field has undergone a drastic shift, rendering his compass useless. Believing the world to be in disarray, Tano’s mindset is set on escape. Juan, however, is less preoccupied with the state of the world and more focused on finding Clara. Their differences in perspective lead to a heated argument, with Tano insisting that Clara is deceased and Juan refusing to accept this harsh reality.
In the closing scene, we catch up with the couple who had stolen Juan’s car. They are seen near a supermarket, siphoning fuel from other vehicles, when a sudden and fatal attack claims their lives instantly.
