, fully titled in Japan, is a Japanese manga series written and illustrated by Junji Ito, appearing as a serial in the weekly manga magazine Big Comic Spirits from 2001 to 2002. Shogakukan collected the chapters into two bound volumes from February to May 2002. The story revolves around a couple, Tadashi and Kaori, as they fight to survive against a mysterious horde of undead fish with metal legs powered by an odor known as the "death stench". The work also includes a pair of bonus stories, titled The Sad Tale of the Principal Post and The Enigma of Amigara Fault.
Viz Media published an English-language translation of the two volumes in North America from September 2003 to March 2004 and re-released it from October 2007 to January 2008. An anime adaptation by Ufotable was released on February 15, 2012.
Plot
Story Tadashi, a young man, and his longtime girlfriend Kaori arrive on the island to enjoy a scuba-diving vacation in Okinawa. After encountering a fish with legs, Kaori, who has a hyper-sensitive sense of smell, becomes irritated by its smell and begs Tadashi to get rid of it. He seals it in a bag, but it manages to escape.
Meanwhile, a crew of fishermen aboard a trawler dragged up several strange-looking fish in the boat's net. Upon trying to inspect the unusual creatures, they discover that the strange fish seem to have legs. The fish then suddenly scuttle away, diving back into the ocean. The next day, large amounts of marine life with legs invade Okinawa, including a legged great white shark which menaces the protagonists. Tadashi and Kaori manage to return to Tokyo, although Kaori becomes irritated and paranoid, claiming to smell the fish. They both encounter the bagged fish they originally encased and present it to his uncle, Doctor Koyanagi.
A short while later, Tadashi returns to find Koyanagi missing an arm. He reveals that he was examining the machine in detail, it used a series of spikes and tubes to latch onto his arm, forcing him to amputate it. The walking machine scuttles into the room, now carrying Koyanagi's arm instead of the fish. Koyanagi explains that the creature is the result of the Imperial Japanese Army's World War II research into a virus that causes its host to produce a deadly and repulsive stench, in a desperate effort to turn the tide of the war. His father developed a "walking machine," which pumps the virus into a host and causes the host to release the gas, which powers the machine's movement; walking machines were built to carry the hosts farther, allowing them to reach and sicken enemy troops. However, during the war, enemy aircraft sunk the ship carrying the prototypes for the walking machines.
Soon, Kaori and Tadashi discover that hordes of marine life with legs are in the process of overrunning Tokyo, having gradually invaded the Kantō region. Having become infected by the gas, Kaori becomes depressed by being subjected to her illness's symptoms and attempts suicide. Tadashi takes her to Koyanagi in an effort to save her; however, on the way home, he is attacked by a giant squid attached to a walking machine and falls into a canal, where he passes out after being injured by thousands of small walking fish.
Awakening a month later at a nearby hospital, Tadashi discovers that Koyanagi has placed Kaori into a custom-built walking machine. Upon switching the machine on, Koyanagi is mortally wounded by Kaori, who quickly escapes. Wandering through the desolate city streets, Tadashi finds that most of the walking fish have decayed, and that walking machines are now carrying land animals, including infected humans. As he continues to make his way through the city, he reaches a circus, where he learns from the ringmaster that the gas appears to be alive, taking on a ghost-like appearance when ignited. Tadashi encounters Kaori and retrieves her from one of the acts at the circus.
As the pair arrive at Koyanagi's lab, Koyanagi's assistant, Ms. Yoshiyama, reveals that the doctor died after succumbing to his wounds. When she attempts to remove the walking machine from Kaori, Koyanagi appears, mutated by the infection and attached to a modified walking machine in the form of an airship that allows him to fly. Kaori notices Tadashi and Ms. Yoshiyama together and attempts to attack her. During the uproar, Koyanagi manages to capture Ms. Yoshiyama and fly away while large groups of walking machines attack Kaori, and Tadashi becomes lost in his attempt to save her.
Shortly afterwards, the circus troupe arrives and uses a human cannon, modified to fire the bodies of deceased infected humans, to damage Koyanagi's airship. Though its envelope is destroyed, the machine deploys a set of wings and escapes. Tadashi encounters a group of students from Kyoto University, who explain that they are immune and that the virus created the walking machines after synthesizing them from shipwrecks. He joins the students in their research to defeat the virus and save humanity. As the group walks together, Tadashi encounters Kaori's burnt remains and remarks that she is free from the smell.
Characters : A young man who enjoys scuba diving. He has a girlfriend named Kaori and an uncle named Koyanagi. At the end he joins a group of university students, who happen to be immune from the death-stench, to create a vaccine to defeat the disease. In the OVA version, instead of Kaori, Tadashi becomes infected and is attached to a custom made walking machine by Koyanagi. The machine later turns against Koyanagi and kills him before escaping. : Tadashi's girlfriend. She has an extremely sensitive nose and becomes very jealous when Tadashi is near other women. Due to her overly sensitive nose, she seems to be able to smell the creatures when they are nearby. However, she is later infected, causing her body to swell up and forces the gas with the "death stench" out of her body. Because of this, she began to think she was disgusting, that Tadashi wouldn't love her if she wasn't beautiful. This, along with the horrible stench, made her attempt suicide. Tadashi then immediately carries her to his uncle Koyanagi's lab for aid, however Koyanagi rigs her up to a custom walking machine and ultimately, she becomes like the walking dead creatures, except with a will of her own. As a walking machine, she is eventually destroyed by a horde of other walking machines that deem the custom walker to be a threat to their survival. In the OVA adaptation, Kaori is switched with Tadashi as the main protagonist. She also possesses the unexplained immunity to the infected creatures' poisons instead of Tadashi. : Tadashi's uncle and an inventor. He discovers it was his father, who died of a heart attack in a factory during a hot summer, was responsible for the creation of the mechanical legs. While dissecting the fish, the legs then clamp onto his arm. He cuts off his arm to prevent the infection from spreading to the rest of his body. He is fascinated by the machine, not caring that he lost an arm to it. He then creates his own version of the walking machine and puts the infected Kaori onto it. He is mortally wounded when he is stabbed by Kaori's walking machine. He then goes to Lab #2 where his father originally died and places himself onto another walking machine that is able to fly. When he notices Tadashi and Ms. Yoshiyama interacting, he attacks them both and captures her. In the OVA version, Koyanagi is shown as an antagonist who went insane and connected an infected Tadashi to the custom Walker. : Assistant of Doctor Koyanagi, who cares for him and Tadashi. When she was seen with Tadashi by Kaori, Kaori tried to attack her. Ms. Yoshiyama then ran outside where she was captured by the Mechanical Koyanagi. She does not appear in the OVA adaptation. The Citrous Circus: A circus troupe who establish themselves in Tokyo following the growing death stench pandemic. While most of the troupe and its animals have been infected by the disease, the seemingly immune ringmaster uses the infected and their walking machines to perform acrobatic shows, and appears to have gone insane as a result of learning of the Death Stench's true nature. Shortly after Koyanagi's flying machine is activated, the Citrous Circus attempts to use a cannon to bring down the machine, but to no avail. The Students: A group of biology students from Kyoto University, who, like Tadashi, are immune to the Death Stench disease. Introduced at the very end of the story, Tadashi met them after the Citrous Circus attempted to attack Doctor Koyanagi's flying machine. After explaining their immunity, it is revealed by the group that the virus responsible for the Death Stench is constructing walking machines from iron-rich shipwrecks, and that they are researching a vaccine that could be capable of stopping the growing pandemic. Tadashi chooses to join the students following this discovery. : A freelance videographer, appears only in the OVA adaption, Kaori met him in the airplane to Tokyo. Follows Kaori just to get to the location of doctor Koyanagi to get his research data. Got infected at the end of the anime before sending Kaori away to a group of survivors. : Friend of Kaori, appears only in the OVA adaption. She is meek and slightly overweight and feels unattractive, appears to be bullied by Erika. Turned into a walker at the end of the anime. : Friend of Kaori, appears only in the OVA adaption, an outgoing and attractive girl who has no difficulty attracting other men, and appears to be picking on Aki all the time. She gets infected by the walking fish early on. During a fight, Aki bludgeoned her to death with an ashtray, but she appears to be alive again later on.
Bonus stories Two unrelated stories, and , are included as a pair of bonus stories, placed at the very end after the conclusion of Gyo. Although both are completely different and unrelated stories (both to each other and to Gyo), they were merged as one chapter altogether. The former is the shorter story, merely consisting of four pages, compared to the latter's thirty-one pages.
The Sad Tale of the Principal Post The story starts with a family celebrating their new home. After noticing that her father is missing, the family's daughter hears him crying out in pain and leads her mother and brother into the basement to look for her father. In horror, the three find the father, who has somehow gotten stuck underneath a huge pillar, one of several that support the house, crushing his body. The mother tries in vain to save her husband but he warns that the pillar that traps him is the principal post of the house; if it is moved, the building will collapse. He tells his family that there is no way he can be saved, and he will sacrifice himself so his family can have their home. That evening the man succumbs to his injuries and dies, and his family places a shrine at the post. Time moves on, but his skeleton remains still trapped underneath the post, along with the mystery of how he got stuck in the first place.
The Enigma of Amigara Fault A huge earthquake has struck an unnamed prefecture, leaving a fault to be discovered by the people on the Amigara mountain (阿弥 ami is a name element derived from Amida Buddha, and 殻 gara means "husk"). People from all over Japan, including a team of scientists, arrive at the mountain to see the strange sight for themselves.
Two hikers, Owaki and Yoshida, meet while hiking, having the same intention to see the fault. The fault is shrouded in mystery; its face being covered in human-shaped holes. It has captured nationwide interest, and several attempts to examine how far the fault goes have all ended in vain. People discussed the origins of the fault, noting that the holes are not natural and must have been dug from the inside of the mountain, but questioning why the holes were made or who would have the technology to make them.