A new liquid organism spawned when humans were exposed to concentrated H-bomb radiation, the H-Man made its way to Tokyo and began a reign of terror by mysteriously melting several people. Initially, authorities dismissed the theory that these disappearances were caused by the H-Man and assumed they were connected to gang activity, but this all changed when they witnessed the H-Man kill an officer at a nightclub. A plan was set into motion to destroy the H-Men where they hid by setting a fire that would spread through all of Tokyo's sewers. The operation was successful, and while the H-Men in Tokyo were exterminated, the possibility still remained that as long as nuclear weapons existed, the H-Man could one day replace mankind as the dominant species on Earth.
In Japanese, this kaijin's name is Ekitai Ningen (液体人間), which translates to Liquid Human or Liquid Man. In international releases, it is given the English name H-Man, a pun on "human" which comes from the abbreviation for the element hydrogen and is likely meant to emulate the term "H-bomb."
The idea for the H-Man was conceived by actor Hideo Unagami during filming of The Mysterians in 1957, when he wrote a story entitled The H-Man Appears about a liquid human spawned by H-bomb radiation. Producer Tomoyuki Tanaka saw potential in Unagami's story and decided to adapt it into a film, but Unagami unexpectedly passed away in November of that year. Takeshi Kimura was hired to adapt Unagami's story into a screenplay, while Ishiro Honda was chosen to direct.
The H-Man is a deadly liquid organism created when the crew of the ship Ryujin Maru II were directly exposed to radiation from a hydrogen bomb detonation. This radiation converted the crewmembers' cells into a new type of organism capable of changing form and disintegrating any other life with which it comes into contact. The H-Men turned on the rest of the crew and melted them, as well as a group of sailors that found the ship and tried to investigate. As if retaining some of their human memories, the H-Men next made their way to Tokyo.
A ship came across the seemingly derelict fishing vessel Ryujin Maru II in the waters off Japan, prompting several crewmembers to come aboard to investigate. Aboard, they found no people but only their clothes, left behind in an odd manner. In the captain's quarters, they found only his clothes in a chair in front of his desk, with his log unexpectedly cut off, suggesting he was attacked when writing. One of the sailors, Daichan, decided to try on the captain's clothes as his annoyed colleagues left him behind. At this time, a strange liquid began to creep across the ground before slithering up Daichan's leg, prompting him to scream. When the sailors went back to check on him, they witnessed him melting away before their very eyes, leaving his clothes behind. They quickly fled in terror to tell the others about what had happened, only to witness the H-Man materialize in the doorway and take on a humanoid shape. Another H-Man appeared from the window and the creatures rushed at the sailors, melting one of them on contact. The remaining four fled back above deck, only for an H-Man to drop onto one of them, Souchan, from above, melting him as well. Only two of the sailors were able to escape and make it back onto their ship. As the others contemplated going onto the Ryujin Maru II to look for the others, the two men begged them not to go, as it was a "ghost ship." They then witnessed countless H-Men materialize aboard the ship's deck.
Months later, in Tokyo, a gangster named Misaki was attacked by an H-Man during a drug deal. When police recovered only his clothes, they determined that he must have ditched them and fled from the police while naked. However, Dr. Masada from Jyoto University had a different theory. He tried to propose to police that Misaki had melted, but his suggestion was laughed off. Meanwhile, a gangster broke into Misaki's apartment to threaten his girlfriend Chikako Arai, believing she knew his whereabouts and that Misaki might be planning to rat on his fellow gangsters. As the intruder left, he was attacked by an H-Man on the street below, leaving his clothes behind as well. With the police still baffled by the disappearances of both Misaki and the intruder, Masada brought several detectives to a hospital where the two sailors who escaped the Ryujin Maru II were being treated for severe radiation poisoning. He had the men tell their story to the detectives, but they did not believe them. Masada explained that even though the two men's ship was never anywhere near irradiated waters, they were both afflicted with serious radiation sickness. He brought the detectives to his lab where he carried out an experiment demonstrating his theory. He exposed a toad to concentrated radiation equivalent to that given off by a hydrogen bomb inside of a machine, which caused the toad to melt into a blue liquid. When placed next to a normal toad, the Liquid Toad slithered toward it and engulfed, it causing it to melt. Masada explained that the toad's cells had been so altered by the radiation that it was no longer a toad, and that it had fed upon the normal toad. The detectives still were not convinced, and continued pursuing the possibility that both disappearances were due to gang activity. Chikako soon sought out Masada and explained that she witnessed her attacker being melted outside her window, but even her testimony was not enough to convince Inspector Tominaga.
The truth was revealed though while detectives were staking out the Cabaret Homura, a nightclub which they believed was a front for a Yakuza drug dealing ring. The H-Man entered through a window and killed one of the club's waiters and a dancer. Chikako, who worked as a singer at the club, discovered the remains of the H-Man's victims and tried to call for help from a phone booth, only for the H-Man to corner her. Two police detectives, Taguchi and Sakata, saw the H-Man trying to enter the phone booth and opened fire on it. The H-Man transitioned into its humanoid shape and confronted the detectives. Sakata charged at it, but was melted on contact. Alerted to the commotion, the detectives and other witnesses came to the scene and watched as the H-Man retreated. Masada's theory had been proven correct, and he subsequently assembled authorities in his lab and repeated the Liquid Toad experiment to demonstrate the threat posed by the H-Man. Masada's superior at the university, Professor Maki, proposed a plan at a government meeting to hopefully exterminate the H-Man. The H-Man was immune to bullets, but Maki proposed that fire and high-voltage electricity should be able to kill it. Because the H-Man was believed to move using the sewers, a plan was formed to dump gasoline into the sewers and set it ablaze, while using high-voltage electricity to block the creatures from traveling further upstream. Citizens in the staging area were evacuated and the plan was carried out, with firefighters on alert to contain the blaze to waterways only. Meanwhile, the gangster Uchida abducted Chikako and brought her into the sewers where he had stashed his drugs. As Uchida tried to escape the sewers with Chikako through a manhole, he witnessed the H-Man slithering along the wall. He had Chikako leave her shirt behind so that it appeared the H-Man had killed her. After seeing Chikako's shirt float out of the sewers, Masada went in after them while Tominaga tried to find him before he was consumed by the fire. As Uchida continued searching for a way out, he was attacked and killed by the H-Man, while Chikako managed to escape and reunite with Masada. However, both the flames and H-Man were encroaching upon them, and they tried to find an escape. Eventually, they came upon Tominaga and a team of soldiers wielding flamethrowers, who helped them to safety and opened fire on the approaching H-Men. An H-Man slithering across the wall was incinerated by their flamethrowers, while two more materialized in their humanoid shapes in the middle of the sewer tunnel. However, they were quickly consumed by both the fire soldiers' flamethrowers and the stream of fire spreading through the sewer and destroyed. Once the fire had spread through all of the sewers, Professor Maki officially declared to authorities that any H-Man in Tokyo was as good as dead. However, he warned, nuclear weapons had created an environment where the H-Man could thrive, and if their use continued, the H-Man could one day rise again and replace humanity as the dominant species on Earth.
The H-Man can dissolve living organisms, including humans, with its touch. How quickly it can do this depends on the method it uses. In its slime form, the H-Man must slowly slither up the body of its prey to gradually dissolve them, while its humanoid form allows it to engulf prey and dissolve them almost instantaneously.
The H-Man is a shape shifter and is able to assume both a humanoid shape or that of an amorphous slime. The H-Man's slime state allows it to move silently and remain hidden, making it easier to surprise prey. Its humanoid form allows it to engulf prey and dissolve them much more quickly.
The H-Man is immune to gunfire, and cannot be attacked physically as its very touch will allow it to disintegrate its attacker.
The H-Man can be killed by incineration or electrocution with a high voltage of electricity.
- Main article: H-Man/Gallery.
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