Jae-hyeok is a middle aged man who works at the local power plant, which is the only thing providing the town with energy, and the provider of most of the jobs. Jae-hyeok lives with his mother, sister in law, and nephew Min-jae. Jae-hyeok wishes to leave the town and the plant behind him and work on a fishing vessel to make money for his family, but is discouraged by everyone he knows. Pyeong-seok is a member of the plant, who tries to get the president to shut down the plant, but he dismisses the claims, saying nothing will happen. One night, the animals of the town mysteriously run into the water. Then, the next day, while Jae-hyeok is working, an earthquake suddenly strikes the town, causing one of the nuclear reactors to overheat. Attempts to cool it down are botched, as water does nothing to stop it. During an attempt to get out, the whole basement caves in, killing most of the crew. Jae-hyeok is one of the few to get out, and continues to get people to safety, until he collapses from nuclear radiation. Meanwhile, the president and his government debate allowing the reactor to vent radioactive particles into the air to relieve pressure from the core. The President insists on evacuating at least those closest to the reactor first. This backfires when the reactor stack explodes from the pressure, leading to a full nuclear meltdown. Meanwhile, the KCDC quarantines the town's residents not far from the reactor. After Jae-hyeok's girlfriend, Yeon-joo, gets proof that the reactor exploded and delivers the news, the KCDC locks the town’s residents in the evacuation center and put up an internet jammer. Rendering their phones useless. Yeon-joo spreads the word and later the residents manage to break out and get back in the buses to continue evacuating. Back at a local hospital, situations grow tense as Jae-hyeok's situation gets worse, and the medical team runs out of medical supplies. The reactor is not cooling down and the only option is to send a team in to blow the floor out from under the spent fuel rods and create a new container in the tank below. Jae-hyeok agrees to a rescue mission, calling a distraught Yeon-joo before getting on a bus back to the town. Jae-hyeok remembers his childhood times before the nuclear disaster, before coming to the plant. By now, the only way to prevent the disaster from irradiating the entire country is to destroy the plant itself. Jae-hyeok willingly goes, having been exposed to too much radiation. Having lost both his father and brother to radiation poisoning, he knows he’s going to die soon and he chooses to go back into the radiation to save his family. The mission encounters a devastating blow when the remote detonators for the bombs won’t work. Someone will need to stay behind and blow the curling of the tank/the floor under the spent fuel rods. It is a suicide mission. As Jae-hyok was a demolition expert in the military, and the only one with experience in explosives, he agrees to do it. After setting up the bombs, and while waiting for the team to get clear, he uses his helmet cam to broadcast a good-bye message to his mother, sister in law, Min-jae, and Yeon-joo, before sacrificing himself by blowing himself up, killing himself and burying the spent fuel rods, saving countless lives. Sometime after this all the other people who went in there with him die from Acute Radiation Sickness. Some time later, Jae-hyeok is considered a hero, and a memorial is set up for the dead. The town's residents are now living in makeshift houses made by the government, and Yeon-joo puts a picture of Jae-hyeok, Yeon-joo, an friends Jin-taek, Soo-won, and Gil-seop onto a memorial gate, before leaving.
Pandora is the first Korean film that has been pre-sold to Netflix. In November 2016, three weeks before the theatrical release, the company acquired exclusive international rights for streaming Pandora in 190 countries.
