An opening text reads: 'Every year 12,000 miners die in work related accidents.'
Many of the town's men dig for gold in the San José mine. Mario (Antonio Banderas) takes extra shifts to support his wife Katty and his daughter Escarlette. Álex (Mario Casas) considers taking a much safer job despite that it may pay much less to ease the mind of his pregnant wife Jessica and his father Don José. Darío (Juan Pablo Raba) would rather sleep on park benches than accept the charity of his estranged sister María (Juliette Binoche). Yonni (Oscar Nunez) entertains his fellow miners with his romantic escapades, while Edison (Jacob Vargas) dresses and behaves like an Elvis impersonator. José (Marco Trevino) doubles as a pastor for the men when they head below ground; shift foreman Luis (Lou Diamond Phillips) has growing concerns about the safety of the San José mine. Gomex (Gustavo Angarita), the crews oldest member, will retire in two weeks.
August 5, 2010. Day 1.
Mario, Álex, Darío, Yonni, Edison, José, Gomex, Luis, and other men board a shuttle bus to the San José mine. While driving through the desert, they pass Carlos (Tenoch Huerta), a Bolivian transplant walking to his first shift at the mine. The bus does not stop to pick him up. Before their shift begins, Luis storms into his boss Castillo's office. While inspecting the stability of the tunnels below ground, he discovered a shard of glass. Luis explains that mirrors were placed between the fissures of the mountain; some of the mirrors have broken, which means the mountain shifted. Luis, concerned about the safety of his men, thinks the mine should be shut down. Castillo disagrees and sends Luis away. Outside, Edison berates Carlos because he comes from Bolivia, where men dig tin but not gold. Everyone climbs aboard a truck, which drives them into the mine through its only entrance and exit: a narrow tunnel. Carlos quickly becomes claustrophobic.
The Machine Shop. Dig site. 1,700 feet below ground. 90°F.
The men set to work. Luis continues to inspect the tunnels and finds more shards of glass. Mario shows Carlos how to operate an excavator. Álex asks Darío if he should take the lower paying job; Darío is hungover and doesnt care. Without warning, the ground begins to shake. Giant boulders rain down upon the miners. Everyone runs to the trucks and drive like mad for the Refuge (dig site, 2,300 feet below ground, 94°F), a place built for miners to wait during a cave in. Tunnels collapse, the trucks careen into giant boulders, and the men are thrown every which way. Above ground, the entrance to the mine gives way in a puff of smoke. All in all, thirty-three workers have been trapped underground.
Above ground, Castillo shuts down the mine site and tries to prevent anyone from leaving. Two miners manage to drive away before Castillo bars the gates; the men call newscasters to report the collapse. The families of the men trapped underground rush to the gates of the San José mine and demand answers. At the presidential palace in the capital city of Santiago, the minister of mining Laurence Golborne (Rodrigo Santoro) tells President Pinera (Bob Gunton) that the mining company cannot handle the rescue expedition. Despite being new to his job, Lauren convinces the president to intervene.
Underground, the miners gather and assess their options. A staggeringly large boulder blocks them off from the roads leading out of the mine. Luis wants the men to go to the Refuge, where there is enough food and water to last thirty men for three days. Mario will not give up so easily. He wants to inspect the ladders that extend up the mines chimneys: if the chimneys have not been blocked, they can all climb out. Álex offers to join him. Luis fails to stop them.
Below ground, Mario and Álex climb the ladders. They quickly discover that the ladders stop halfway up the chimney. Their employers never bothered to finish them. Luis discovers that the communication radios installed in the Refuge were never finished. Darío attacks Yonni to get access to the food rations. The men discover eighteen cans of tuna, a few packets of cookies, and some milk cartons. Mario confronts Luis, who knew the ladders were never finished. Luis has given up hope: it took a century for the miners to dig this deep, and the company that owns the mine will never pay for their rescue. He believes they will die underground. Mario and Luis almost come to blows, but when Darío begins to eat the rations, a riot erupts. Mario calms the other men down and earns their respect: they put him in charge of the rations.
Above ground, Laurence arrives at the mine site. María confronts him and will not let him pass until he has sworn he will save the men trapped in the mine. Castillo tells Laurence he tried to send a team of rescuers down a chimney but that it collapsed. Its too dangerous to attempt another rescue. When Laurence delivers the news to the miners families, María attacks him for failing them. President Pinera calls upon André Sougarret, a well-respected mining engineer. André tells Laurence that, even if they began digging immediately, it would take about eight days to reach the trapped men. To complicate matters, the rockbed could cause the drills to veer away from the Refuge. Reaching the men will be a challenge, and they dont have any time to spare.
Below ground, Mario distributes meager rations. The men manage to restore the Refuges lights, which raises their spirits. When they hear the drills and realize they will be rescued, their moods rise.
The drills have been working nonstop but break frequently because of the incredibly hard rock of the mountain. André becomes impatient with Laurence when the other man asks him too many questions. The families of the miners have set up camp outside of the mine site. Laurence, unable to answer whether the trapped men are still alive, feels helpless when he addresses them. He organizes a camp that will provide shelter, food, medical attention, and schooling for the rescuers and the families of the trapped miners. María finds Laurence and thanks him for keeping his promise. Below ground, Darío struggles through withdrawal. José comforts and prays with him.
Camp Hope is up and running. Katty and Escarlette cook food; Jessica teaches the children of the miners; Yonnis wife and mistress come to blows over who will be the one to greet him.
A drill finally reaches the depth of the Refuge. Above ground, Laurence and André and the miners families wait anxiously for the machinery to break through the rock. Below ground, the men hear the drills approach and rejoice. Their celebration ends abruptly, when they realize the drill has bypassed the Refuge. Álex breaks down and runs to a ledge within the cavern. Mario convinces him not to jump by reminding him of his responsibilities as a father. Days pass, and hope dwindles. The miners eat the last of their rations and imagine it is a feast attended by their loved ones. Above ground, André tells Laurence that the men are probably dead. He's giving up. Laurence is furious, but after talking with María, he has an idea: based on their past miscalculations, they should direct the drills along the fissures in the rock. When he explains his plan to André, the engineer realizes its brilliant.
Mario walks through the Refuge and sees how badly the men are doing. Álex is talking to himself. José has difficulty breathing. Carlos seems lost in his own mind. To his astonishment, one of the drills breaks through the cavern ceiling. Mario calls the other men, and they bang upon the drill. Aboveground, Laurence hears the noise. The miners attach a note to the drill, which President Pinera reads to the miners families: all thirty-three men are alive. Everyone rejoices. Even Yonni's wife and mistress embrace. André tells Laurence that extracting the men still presents a challenge: nothing like this has been attempted before.
More days pass. The rescue team lowers a camera into the Refuge, allowing the men to communicate with the world above. Now that they've found the men, they can send them food and more: iPods, magazines, new clothes. The men's health improves, but they grow tired of living in close quarters. Mario quickly becomes the face of the miners, and they resent his rise to fame -- especially when Yonni reads in a paper that Super Mario has been offered a book deal. Mario does not respond to his friends criticisms well and takes credit for keeping them alive. Edison leads a coup and ousts Mario from power. Above ground, the president is furious that the drills keep breaking, delaying the miners rescue. Below ground, Darío finds Mario. He confesses he doesn't know what to say to María once they're rescued: she abandoned their family, and him, when he was young. Mario tells him to forgive María and pray to god she forgives him. Edison awakens and believes Carlos has stolen his iPod. When he tries to beat Carlos, Carlos pulls a knife on him. Mario breaks up their fight and apologizes for letting his fame get to his head. All of the men, including Edison and Carlos, embrace Mario and welcome him back into the fold.
Luis hears the drills approach and realizes it will hit an iron support beam if it continues on its current path. Hitting the beam will break the drill and delay their rescue again. The miners tell Laurence and André that they will have to use a controlled explosion to take out the iron beam underground. They're willing to assume that risk. Above ground, the families know the men will be rescued soon. Jessica goes into labor but refuses to leave the mine site. Yonni's wife decides to leave him (and Camp Hope) while his mistress is invited to the extraction site by María. An extraction capsule will carry the miners out one by one. Laurence and André tells the miners that, due to the mountains instability, there is not enough time to enforce the shaft that the capsule will travel. If anything happens as the capsule goes down and up, then it might be impossible to get the miners out. The first man will be in the most danger but might also be the only man to get out.
October 13, 2010.
The extraction capsule reaches the Refuge. Álex is chosen to be the first one taken out. He tells his friends he will see them above ground. The extraction goes off without a hitch, and Álex emerges from the capsule to find his father, Jessica, and their newborn daughter waiting for him. The rest of the men emerge one-by-one. Mario whips the crowd into a frenzy. Edison and Yonni strikes poses. President Pinera embraces Laurence and congratulates him. Darío and Mario hug each other. Luis is the last man to be taken up, and the film ends as he steps into the capsule.
The San José Mining Company was found not guilty of criminal negligence, and the miners were never compensated. Nonetheless, they remain brothers to this day.