7 Seeds

A shy girl named Natsu Iwashimizu awakes during a storm and is taken aboard a inflatable boat with three others. No-one recalls what happened, and they paddle their way to a nearby rocky island. The others introduce themselves as Arashi Aota, Semimaru Asai and the older Botan Saotome. The group then look for water and food. Meanwhile another group have also landed on an island; Hana Sugurono, Mansaku Tsunomata, Fujiko Amacha, Haru Yukima, Momotaro Nobi, Chisa Taiami, Hibari Nigusa and their leader, the arrogant and belligerent Dosei Yanagi. They encounter large aggressive insects and decide to leave on the raft they constructed, however they are caught in a storm and are shipwrecked back on the same island. While exploring, Yanagi falls into a group of insects although he returns later, seemingly unharmed. Elsewhere another group, awaken from cryogenic sleep, and when confronted by their erstwhile leader, Unami, they draw guns and shoot him.

Arashi falls ill after eating fungi collected by Natsu, however he soon recovers. The team continues its search for edible food, but Natsu and Arashi are captured by carnivorous plants and attacked by large rodents, however they are saved by the arrival of Mozu (Kaname Mozunoto) who was separated from his group. He explains that they are part of a government survival project and Botan explains the 7 Seeds project, but Arashi refuses to believe it and misses his girlfriend Hana. Meanwhile, Yanagi leads his group back to the waterfall where they encountered the giant insects assuring them that it will be safe. He then leads them into an underground tunnel, but it's a trap as he has been impregnated with insect larvae. However, he sets himself alight to save the others, and tells them to search for the 7 Fujis. The group returns to the shore and build another raft, and prepare to sail to the closest Fuji, Mt. Ogino Fuji.

Botan's group encounters three people being menaced by a crocodile in a pond, and she immediately jumps in to save them. Botan explains that they are the remainder of Summer Team B; Matsuri Tendō, Chimaki Yamori and Hotaru Kusakuri. Natsu realizes their island in a lake, so they build a raft and leave to find the outer shore. They arrive and begin the search for food, but also find the Nagasaki peace statue underwater. Botan decides to head for the nearest Fuji, Mt. Bungo Fuji, also known as Mt. Yufu. While walking, Natsu accidentally come across the entrance to one of the sealed caches containing the necessary materials for survival and self-sufficiency. Chimaki decides to visit his nearby home town of Kumamoto, and Natsu and Arashi accompany him, however they find that it is underwater. Arashi decides to travel to his home in Tokyo, vainly hoping to find his girlfriend Hana. Natsu initially accompanies him, but Semimaru follows and joins them. Along the way, they encounter some other humans. Meanwhile, the Spring team discover that they are near the ruins of Yokohama.

Arashi, Natsu and Semimaru realize that they have stumbled upon the Fall Team settlement which is above one of the sealed caches in the former Kobe region. The team have already been there for three years, but they are dominated by Akiwo Haza and Ran Shishigaki who ruthlessly allocate tasks to other members of the team and dominate the guide Ryoya Izayoi. When Semimaru tries to steal some food, the three travelers are tied up. Akiwo and Ran have banned sex in the team to avoid fulfilling the role for which they were selected. Ryoya, frees the three captives, but plans to poison them and everyone else because he feels that the 7 Seeds project has failed, but Semimaru stops him. They leave, but later, Ryoya helps them launch their inflatable boat to continue their journey towards Eastern Japan. They find another entrance to a sealed cache which is at either Mt. Ogino Fuji or Mt. Kyogatake, but is it is flooded and of little use. Meanwhile, Hana and Haru of the Spring Team paddle their inflatable through the partially submerged ruins of Yokohama. They camp the night in an abandoned church, and return to the team the next day. As Arashi's group settle for the night, they are watched by a bearded man.

Arashi decides to search underwater for signs of humans, but is suddenly confronted by a giant fish. When it tries to attack him, it is suddenly killed by a huge spear thrown by the bearded man accompanied by two wild dogs. His name is Takahiro Aramaki, the only survivor of the Winter Team who died fifteen years ago. Meanwhile, Hana and the Spring Team find the same flooded cache as Arashi, including food, books and supplies that are still intact. After they find a letter written by Natsu to any other survivors, Mansaku Tsunomata states that they must accept their current situation and survive. Fearing Takahiro, Arashi, Natsu and Semimaru leave during the night. Takihiro finds himself alone again with his dogs. He recalls how four of his team were killed by a saber-toothed tiger-like cat soon after emerging. He befriended a wild dog which followed them, but Fubuki was later killed by the same tiger while saving Takahiro and Mitsuru. She later froze to death while dancing in the snow. The dog died from her wounds, but her two pups became the foundation of his pack of dogs. Back in the present, Takahiro sees Hana being chased by a dinosaur-like creature and he uses his dogs to save her.

Takahiro is taken in by the Spring Team, although there is some mistrust. He tells Hana about the three people he met and she thinks one may be Arashi. Hana accidentally touches a plant which Takahiro says are poisonous, and she begins to develop symptoms. She decides to avoid infecting the others and leaves alone to find Arashi, but she is knocked into the water by a giant fish. She decides that life is not worth living, but is rescued by Takahiro who takes her to the island on which Summer Team B first landed. However, her health continues to deteriorate, and she wanders off alone expecting to die. When she sees a message carved in the rock by Arashi, she regains the will to live. Takahiro realizes that salt somewhat neutralizes the poison and finds a salty pond to help Hana recover. Takahiro, Haru and Hana return to the Fall Team’s settlement, but find it abandoned and covered in volcanic ash. Meanwhile, Arashi and his group find another cache and a sailing boat.

Arashi, Natsu and Semimaru decide it is time to return to Kyushu and rejoin their team using the sailing boat. Meanwhile, Takahiro, Haru and Hana find a tunnel entrance and two members of the Fall Team underground. One captures Haru who insists that he has been hearing the sound of a motor. When Takahiro's group go to find them, Akiwo and Ran and Team Fall take their inflatable raft and move further into the underground system which appears to be an evacuation complex. They find that power is available and they access the computer system. Meanwhile Takahiro's group also explore another part of the complex where they find a body and a diary. The diary details the experience of Mark Ibaraki, a ventriloquist who was hired by Hana's father, Takashi Sugurono, along with other entertainers for the Ryugu Shelter which was described as a new underground theme park. Soon the meteorites hit earth, destroying the surface. Mark realized that they were engaged to distract the survivors. The facility was not able to cope with the disaster, and eventually after food supplies ran out. Then a deadly infection called the Acari X virus spread throughout the facility and it was sealed off. The last survivors were frozen to death to prevent the disease spreading and Mark was the last to die, taking his own life. As the 7 Seeds survivors emerge from the complex they are confronted by armed people wearing protective clothing and are accused of spreading the X virus. As Ran is about to be shot, Ryoya leaps in front of her and is shot instead.

The armed group decide that the X virus has probably already been released, and leave the teams to their own devices. As Ryoya dies, he reveals to Hana that it was Arashi who inspired him to survive and help his team. When they arrive back at Team Spring’s camp, they find it destroyed and Fujiko Amacha, Mansaku Tsunomata, Chisa Taiami and Momota Nobi missing. Takahiro suggests they travel on to his former camp. Meanwhile, Arashi, Natsu and Semimaru learn how to sail the boat and find a girl who looks like Hotaru floating in the water. Her name is Hibari from the Spring Team who says that Hotaru is dying. Elsewhere, Momota from Team Spring is found by Summer Team A but Madonna casually tests food and medical treatments on him rather than her own team. They then use him as bait to attract predators which they can kill for food. Ran and the others come across Summer Team A's well designed camp and realize they were who ones who shot Ryoya. Away from the camp, Koruri comes across Haru making music while flying her hang glider. Takahiro creates a diversion while Hana attempts to rescue Momota, but they are caught. In retaliation, the group capture Koruri and offer to trade her for Momota. Suddenly, Takahiro and the camp is attacked by a colony of white carnivorous bats, and everyone cooperates to defeat them.

Slowly, Summer Team A and the other group begin to cooperate, although there is still some mistrust between them. Together they successfully devise a plan to get rid of the bat colony using music made by Haru. They form an uneasy truce and Summer Team A also help treat the injuries of the others, including Kurumi Shikano who is pregnant with Ryusei Ogiwara's child. When Ango discovers that Hana is the daughter of Professor Takashi, he tells everyone about the program which created the Summer Team A, and how he protected his younger friend Shigaru. However, he discovered that those who failed were not returned to the outside world, but killed. On board the boat, Arashi, Natsu and Semimaru learn that Hotaru is a cousin of Hibari.

After his discovery about the training program, Ango had to reconcile himself that only the chosen seven would leave alive and he focused completely on his survival skills. Towards the end of training he found that items were sabotaged causing the inattentive students to sustain accidents. After the school caught fire, he realized that only the seven students who survived would be chosen. He also heard that one of the group will be a "reaper". Towards the end, they are both told that only he or Shigaru will be chosen from their group, but they remained friends to the end when Shigaru sacrificed himself to save Ango although Ryo caused his death. Finally when the seven surviving students are selected to be Team Summer A members, the instructors are surprised that they are not in a mood to celebrate following the deaths of their comrades. Consequently, when they awake from their hibernation they kill Umami, the instructor selected to lead them. Ango finishes his story, but shows his resentment to Hana because of her association with Professor Takashi and his team.

Ango's animosity towards Hana increases, and she becomes convinced that Ango will kill her if she stays in the village. She decides to leave, and Takahiro offers to leave with her as does Haru. Ango tries to rape Hana, but he is stopped by Ayu and Hana realizes that Arashi is no longer there to protect her. Hana prepares to leave that night. Meanwhile, the boat of Arashi and the others becomes snagged and they make landfall near the abandoned former settlement of the Fall Team. Natsu finds a note to Arashi from Hana, but she hesitates to show him. Later, Natsu and Semimaru encounter Matsuri and who tells them that Botan and Hibari are in danger. Kaname Mozunoto rescues them and Hibari and Hotaru meet for the first time. Later, Natsu gives Hana's note to Arashi.

Ryo orders Hana to join the group in searching for a water source underground, putting her in a vulnerable position. In the caves, Ryo, Hana and Ayu descend further looking for water, and Ryo tells Hana about her father. However he cuts her rope, letting her fall to her death to because he fears that she is causing Ango to become mentally unstable. When Ryo and Ayu return, the others decide to try to find Hana. Meanwhile Hana survived the fall and continues to look for water and Haru plays a flute to signal their location in case she is still alive. Elsewhere in the cave, Ango hears an imaginary voice blaming him for Shigaru’s death, and when he come across Hana. He pushes her into the swirling water just as the others reach them. As they prepare to save her, she yells that Ryo is not to be trusted. Just as Koruri reaches her, Hana is swept away. Gengorou unsuccessfully tries to save her. When they return to the camp, Takihiro approaches Ryo and accuses him of being a murderer.