Trama

Two parallel stories about characters trapped in illogical endless spaces: two brothers and a detective locked on an infinite staircase, and a family locked on an infinite road - for a very long time.

Small-time criminal Carlos comes home to find his younger brother, Oliver, agitated. Before Oliver can explain his behavior, rogue cop Marcos emerges from hiding and places both brothers under arrest. Oliver explains that he has confessed under duress and begs forgiveness. Carlos demands to see a warrant. Marco admits he does not have one and attempts to take them to the police station at gunpoint. They overpower him and flee down their apartment complex's stairs. While chasing them, Marco shoots Carlos in the leg. Marco seems surprised by his action and is further worried when he hears a loud noise in the distance. Carlos and Oliver surrender to Marcos, who refuses to take them to a hospital.

Marco is horrified when the stairs turn out to be endless, looping in on themselves. Oliver applies first aid to his brother but can only watch as Carlos bleeds to death the next day. Before he dies, Carlos urges Oliver to appreciate the present, something he could never do. As Oliver mourns Carlos' death, Marco becomes shaken when he sees that a vending machine on the stairwell has become restocked, exactly as it was 24 hours ago. Enraged by Marco's callousness, Oliver disarms him and threatens to kill him with his pistol. Marco insists that he did not consciously choose to shoot Carlos, and the two argue over the metaphysics of their situation.

Elsewhere, Sandra and her two children, Daniel and Camila, prepare to visit her ex-husband. Although her new husband, Roberto, is anxious about the trip, Sandra reassures him the long drive will give him a chance to bond with her children. On the way, they stop at a gas station, where Roberto carelessly offers fruit juice to Camila. Camila has an allergic reaction to it, which brings on an asthma attack. After Roberto accidentally destroys her inhaler, an accident he insists was fated to happen, a loud explosion sounds in the distance. Sandra asks Daniel to retrieve the backup inhaler, but he reveals that he forgot to pack it. Panicking, Sandra insists that Roberto turn around and return home. After passing the same gas station repeatedly, they realize the road endlessly repeats the same stretch.

Roberto exits the car and walks off through the brush to seek help. Without access to her inhaler, Camila dies. Believing herself to be stuck in a nightmare, Sandra abandons her children and drives off, vainly attempting to wake herself. Daniel picks up his sister's body and begins walking down the road in the opposite direction. All converge to the same spot and give up hope of escape. Thirty-five years later, both groups are still stuck in their respective locations. Each day, everyone finds a fresh copy of all their possessions. Over the decades, these items gather into towering piles as the two groups attempt to live their lives.

Sandra and Roberto, now elderly, have animalistic sex, Daniel lives on his own without much interaction with them, and Oliver leads the elderly Marco in rituals worshiping Carlos' skeleton. After Sandra dies, Roberto and Daniel hold a funeral, where Roberto is struck by a moment of lucidity as he, too, nears death. He says he now understands why they are stuck. Marco and Roberto jointly reveal that none of this is real, but an alternate dimension to their real lives. An elderly Roberto explains that when he was a 10 year-old boy, he was in another incident stuck on a raft. At the same time, an elderly Marco explains that he is really Daniel, the 10 year-old boy from the incident of the infinite road, thus explaining the cycle of incidents/new dimensions. These dimensions split off from reality and are stuck in a time loop. They are brought on by tragedy, and the emotions that the inhabitants feel are fed back to people in the real world. The younger person stuck in an incident fares better than the older person. Therefore, younger people in the real life have more happiness and fortune than older people, who experience more sadness and misfortune.

As he dies, Roberto urges Daniel to break the cycle of creating new dimensions by refusing to follow his fate. Marco/Daniel urges Oliver to break the cycle as well by refusing to follow his fate. Daniel and Oliver find they are now free to leave their dimension. Each initially hesitates but follows his fate. Daniel enters a police car and becomes Marco, off to arrest Oliver and Carlos. Oliver leaves his apartment complex, becoming a Russian bellhop who operates an elevator for a bride and groom. He sets in motion an accidental death for the groom, trapping himself and the bride in a new dimension for thirty-five years.