Hypnos (Digimon)


HYPNOS, hard at work, tracing another Bio-Emergence.

Hypnos is the name of a fictional organization from the Digimon Tamers TV series. This covert agency is believed to be named after the title of a minor tale by horror author H. P. Lovecraft and Hypnos the Greek God of Sleep.


Hypnos' original purpose was to monitor electronic communications of half the Earth for the Japanese government. Because of the legal issues of violating privacy, Hypnos was kept secret from the public. However, Hypnos discovered Digimon (termed "Wild Ones") who entered the real world. As a result, the agency's new objective is to detect Digimon when they Bio-Emerge in the real world and to prevent it if possible. If a Digimon does manage to crossover, Hypnos would try to capture the Wild One and study it. Another function of the agency is to prevent media leaks about Digimon, as well as cover up incidents (such as creating cover stories) that involve Digimon. Apparently Mitsuo Yamaki, the head of Hypnos, had an agenda to eliminate Digimon once and for all.

However, their efforts at first proved unsuccessful. As time went on, they developed new and better methods of attacking Digimon, but these techniques proved ineffective against the Devas. In their efforts to better understand and defeat the Digimon, Hypnos recruited the computer programmers, the Monster Makers, who originally made the Digimon, attempting to use their knowledge to create a successful anti-Digimon weapon.

After the Tamers entered the Digital World, Hypnos' objectives changed: they now sought only to bring the kids home. This new realization came after Hypnos' leadership realized that not all the Digimon were evil. Eventually, their efforts allowed the children and their Digimon to return to the real world. Hypnos later helped in the battle against the D-Reaper.

Hypnos is covertly headquartered in the Tokyo Metropolitan Government Building, which also houses the Hypnos computer system, as well as several labs for research. The agency employs scientists, operators, and computer programmers, as well as several field agents. Also at Hypnos' disposal are unmarked black vans and helicopters, used for investigation and combating Digimon. Since Hypnos is a government agency, Yamaki reports to four officials, presumably his superiors in the Japanese Government, and to the Chief Cabinet Secretary (voiced by Dave Mallow in the US dub).

Mitsuo Yamaki and Hypnos


Mitsuo Yamaki

While his sinister, black-suited exterior seems to present Yamaki as little more than a basic G-man, those shades hide the mind of an electronics genius. Yamaki was responsible for designing the Hypnos system, which keeps a constant watch over the Earth’s electronic communications network, secretly monitoring and recording information and acts as section chief to the organisation named for his creation. Yamaki apparently also worked on other government projects before. When Hypnos became aware of Digimon existing autonomously within the network, protocols were immediately established to deal with these Wild Ones, as they were code-named, as they began to Bio-Emerge into the Real World. Yamaki, a stiff man of few outward emotions, grew to hate the creatures, viewing them embodiments of chaos and disorder, a danger to humanity, and mere faulty programs. Among Yamaki’s traits is his compulsion to flick open and close the silver Zippo lighter he always carries – it’s generally believed he’s attempting to quit smoking, and flicking the lighter is a possibly-unconscious nervous action caused by wanting a cigarette (due to stress, most of the time). He is involved in a relationship with Hypnos chief systems operator, Riley Ootori.

When the Wild One known as Guilmon Bio-Emerged, Yamaki instructed a tracer to be kept on him, to see what he would do. The following day, after Guilmon had battled Renamon in Shinjuku Park, Yamaki headed up the team that examined the battlefield and found a Modify Card lying on the ground.

Yamaki and his Hypnos underlings continued to observe the Bio-Emergence of other Wild Ones, only to have the Tamers and their Digimon defeat them. While on another field mission, Yamaki was called back to headquarters by Tally at the request of his superior, the Chief Cabinet Secretary, to fully explain the nature of Hypnos. The secretary made it clear that Hypnos was to remain a secret from the public, and that all Digimon connection to the Real World was to be eliminated. That night, when Guilmon slipped into a warp between Earth and the Digital World, Hypnos picked up the signal from the tunnel under the park and Yamaki, in direct defiance of orders from above, uploaded his Yuggoth deletion program into the Hypnos system and had Riley target the tunnel with it. The Tamers just managed to rescue Guilmon before the Yuggoth struck.

When a Devidramon Bio-Emerged and flew over the city in clear view of the populace, Yamaki viewed the Digimon’s audacity as a personal insult. There was little action that could be taken, however, but when Growlmon destroyed Devidramon, Yamaki charged Riley with inventing a cover story for the incident.

Hypnos was unable to stop IceDevimon from Bio-Emerging but seemed to have more luck with Musyamon, who was apparently destroyed by Yuggoth. It was not to be, however – Musyamon’s data survived and his voice was heard in Hypnos headquarters, declaring his desire for revenge. He reappeared the following day, and destroyed Yuggoth when it attempted to target him. Yamaki headed for the Shinjuku Guard Rail, the site of Musyamon’s Bio-Emergence, and observed the battle from afar as Takato, Henry and their Digimon defeated Musyamon. Yamaki was subsequently able to identify the two boys by name and tracked them down to deliver a warning – stop playing their dangerous game. Jeri’s arrival distracted the boys and Yamaki departed, only to have Henry pursue him but, unsurprisingly, the boy failed to catch him. That evening, he observed the Tamers’ battle with Harpymon and decided that it was time to end things.

Yamaki confronted Takato face-to-face once more as he and another team of Hypnos operatives captured a DarkLizardmon that Takato and Guilmon had just defeated. During the examination of DarkLizardmon, Yamaki pushed the scientists to increase the intensity of the scan, destroying DarkLizardmon’s form and then instructed them to delete her remaining data. In a subsequent video conference with the government operatives above him, Yamaki persuaded them to allow him to activate his Juggernaut program (Shaggai), which tore open a vortex between the Real World and the Digital World and began pulling Digimon through it, returning them to where they came from. Yamaki and Takato faced off once more but Yamaki simply walked away from the boy... only to be informed that an anomaly had infiltrated the Juggernaut, allowing something to come through from the other side. That “something” was Mihiramon, the tiger Deva, and his appearance on Earth tested Yamaki’s sanity, as he took out his frustrations on Henry, throttling him – only to deem him not worth it. Staggering away, Yamaki returned a short time later, having organised a military strike. Attack choppers opened fire on Mihiramon atop the Hypnos towers, to no effect, but then, Growlmon Matrix Digivolved to WarGrowlmon and destroyed Mihiramon, much to Yamaki’s surprise, forcing him to realise that the kids viewed the situation as more than just a game.

Yamaki was, unfortunately, powerless to stop further Devas using the Juggernaut to enter the Real World and took action by re-uniting the Monster Makers, the original programming team that created Digimon, including Henry’s father, Janyu/Tao, in order to learn more about Digimon and, in doing so, how to destroy them. Prior to this reunion, the horse Deva, Indramon, Bio-Emerged and Yamaki attempted to stop him with an underpowered Juggernaut activation. It failed, but Indramon decided it was time to leave. Subsequently, a strange binary code communication found its way through the Hypnos computers – the Devas communicating with each other – and Yamaki laughed at the simplicity of it. The Monster Makers were then brought together, only to have the meeting coincide with Indramon's reappearance. Yamaki took the chance to explain the mechanics of Digimon Bio-Emergence to Janyu but military strikes on the creature proved fruitless, meaning it was once again WarGrowlmon who stepped up to destroy the Deva.

When the gargantuan pig Deva, Vikaralamon, Bio-Emerged in Shinjuku, Yamaki took it personally – such a massive scale event couldn’t be hidden from the public and it was his responsibility to stop it. The Juggernaut program was once again activated at full power, despite the pleas of Janyu Wong, and Vikaralamon – and the Tamers’ Digimon – were caught in its power. However, the monkey Deva, Makuramon, chose that moment to reveal himself, using the binary code language to communicate directly with Hypnos and warn them that they were getting in his way. He instigated an implosion that crashed the Juggernaut data stream and destroyed a substantial portion of the towers. In a fit of frustration Yamaki attempted to force some of the technicians to stay but no one in their right mind would listen to him and everyone evacuated. Out of loyalty, and as would later be revealed love, Riley stayed by him, but when he realised there was nothing that could be done, he silently told her to leave. Yamaki remained in the building as it was consumed by an explosion.

Yamaki survived the attack but for him, the outcome was perhaps worse than death - the Digimon had apparently won, and he was fired. Wallowing in self-pity – and cigarettes – Yamaki was snapped out of his funk by Riley, who convinced him that there was still some good he could do. (It was subtly revealed at that point that Yamaki and Riley were living together and carrying on an after-hours relationship. Series creator Chiaki J. Konaka himself noted that it surprised the rest of the writing staff when he revealed that Yamaki and Riley were involved romantically.) The Tamers had planned to enter the Digital World to rescue Calumon from Makuramon’s clutches and Yamaki gave them a comm device before they left so they could stay in contact with him.

Unfortunately, the Tamers soon discovered that the device didn’t work in the Digital World – except during a storm created by the hasty re-activation of the unstable Hypnos and Juggernaut system by the Head of National Security. The Chief Cabinet Secretary opposed the move and, when the system began to run out of control, called in Yamaki and Riley to put things to rights. The two of them were the only ones able to pull the system back under control and they were reinstated for it. Subsequently, Yamaki called the Monster Makers and all the kids’ families together to explain the situation to them. During the meeting, he received another message from Takato and Henry.

Not long after, when Janyu took Suzie to play in the park, Yamaki met with him there and they discussed the history of the Digimon project – but were powerless to stop Suzie from being pulled into the Digital World, where she was reunited with her big brother and the other Tamers.

Things took a turn for the worse when the Chief Cabinet Secretary restarted the Hypnos program again with untrained replacement personnel. Hoping to use the Juggernaut system to finish the job that Yamaki had started, they reactivated the digital weapon and it began to wreak havoc once again on both the Real and Digital Worlds. With the Juggernaut Core still unstable after the attack on Hypnos HQ by Makuramon the system ran out of control and put the Tamers in the Digital World in grave danger. Yamaki and Riley quickly showed up to stop the system before any serious damage could be done. Yamaki - and by proxy, his team - were fully reinstated after saving everyone and shutting down the Juggernaut again. With his government privileges restored he and the Hypnos were free to use all their resources to help keep track of and aid the Tamers in the Digital World.

Events in the Digital World proceeded apace, as the Tamers battled Beelzemon and Zhuqiaomon, lost Leomon and discovered Biomerging. Meanwhile, on Earth, Yamaki made all of Hypnos’s facilities available to the Monster Makers to construct an "ark" that would bring the Tamers home. Guided by Yamaki via the comm device, Takato led the Tamers back to the surface layer of the Digital World, and onto the ark. An attack by the deadly D-Reaper on the Hypnos central processor almost derailed the rescue attempt but the Monster Makers were able to harness the processing power of computers all over the planet to make it work. Yamaki was so impressed by their sheer skill and ability that he even became calm enough to set down his lighter. The ark materialised in Shinjuku Park and the Tamers with it.

The fight was not over. The D-Reaper had pursued the Tamers back to Earth via Hypnos and engulfed a large portion of Shinjuku in its mass. Yamaki, Riley, Tally and the Monster Makers were forced out of the Hypnos towers and had to operate out of one of the organisation’s vans. Later, they established a temporary base in the Tokyo Opera Tower and Yamaki, Riley and Tally went to the Matsuki bakery to meet with the Tamers and then watch as they battled one of the D-Reaper’s Pendulum Feet Agents.

As everyone made their own plans for dealing with the situation, Yamaki was offered a moment to reflect on his actions. Riley realised that he was blaming himself for everything that had happened, and tried to console him, telling him that he was just the first man who had tried to control the network – the uncontrollable. Yamaki laughed, telling her he had no intention of being the first in a line of fools. During a subsequent battle between the Tamers and more of the D-Reaper’s Agents, Yamaki was shocked to receive a message on his comm device from the ark, asking for instructions – the Digimon core code used to create it had made it self aware, and it now resided in the Digital World, low on power. Yamaki turned to Daisy for her help in establishing a connection with the ark, and she succeeded, redesigning it into Grani. Later, when another battle broke out, Riley was able to hack into the D-Reaper’s signal and utilize its ability to view through layers of data, revealing to everyone that the Tamers had actually merged with their Digimon. Yamaki was overcome with shock at the revelation and blamed himself for allowing the conflict to reach this point. He quickly regained his composure, however, and hit upon the idea of using a satellite to directly communicate with Takato and direct him to use Grani’s Yuggoth Blaster on the D-Reaper.

The end result of the battle was that the D-Reaper evolved into the Mother D-Reaper, forcing everyone to retreat to the Tsukuba Communications Research Centre. There, Yamaki co-ordinated Operation: Doodlebug, the final plan to defeat the D-Reaper. When the Tamers returned to Shinjuku to face off one last time with the D-Reaper, Yamaki, Janyu and Dolphin directed Henry to activate the Juggernaut within the D-Reaper’s portal between the Real World and the Digital World and to reverse the flow of the vortex, pulling in the D-Reaper and reverting it to it’s original harmless form – but Yamaki was forced to conceal the truth, that the Juggernaut would also return the Tamers’ Digimon to the Digital World.

Some time later, as Takato reflected over the events that followed the D-Reaper’s defeat, Yamaki and Riley were shown being served in the Matsuki bakery.

Some months later, when Locomon made his disruptive appearance in Tokyo, Yamaki quickly took control of the situation. Commandeering control of the railway lines for the city and co-ordinating with Riley and Talley back at Hypnos HQ, he was able to manipulate tracks and points to keep Locomon clear of occupied lines and steer him towards Ichigaya station, in hopes of sending him back to the Digital World through a warp that had opened there. Unfortunately, that was precisely where Locomon wanted to go, and Parasimon, a spider-like Digimon controlling him, used the warp to summon a massive swarm of his kind to Earth, which were defeated in a massive battle with the Tamers and their Digimon.


During their attempts to seek and destroy Digimon, who were composed of data, Hypnos developed two programs meant to serve that purpose.


Effectively just a way of tracking Digimon before they bio-emerge, this program allows Hypnos to find the coordinates in the real world where the digital field will form. This is the first program seen used by Hypnos in the first episode.


Essentially a blast of virtual energy, the Yuggoth program locks onto and strikes Digimon, supposedly deleting them. But, in some cases, the digimon that was bio-emerging was able to withstand, and disable Yuggoth temporarily. The Yuggoth program was later downloaded into Gallantmon's vehicle Grani as a new attack, the "Yuggoth Blaster".

Juggernaut (Shaggai)

The most powerful of Hypnos' weapons, the Juggernaut program is a digital vortex that draws in all data nearby, including Digimon. The program nearly succeeded in destroying many Digimon, but inadvertently allowed Mihiramon, one of the Devas, to pass into the human world. The Juggernaut's subsequent uses were equally ineffective, until it was downloaded into Terriermon. As MegaGargomon, he and Henry Wong used it as part of Operation Doodlebug, regressing the D-Reaper back to its original harmless state.

Ark Program

A transport program created by Hypnos with the Monster Makers' help, the Ark's purpose was to bring the Tamers home from the Digital World. However, the program evolved beyond its original purpose, actually developing intelligence. Later, when the Tamers and their Digimon were locked in battle with the D-Reaper, Hypnos recovered and modified the Ark into an attack vehicle, and attempted to materialize it in the human world. However, it was unsuccessful until Gallantmon channeled his energy into it, creating Grani.


  • Mitsuo Yamaki - Head of Hypnos. He was voiced by Susumu Chiba (Japan) and Steven Blum (US).
  • Reika Ootori (Ootori Reika) / Riley Ootori - Chief System Operator. Voiced by Tifanie Christun (English, Series) and Philece Sampler (English, Movie).
  • Megumi Onodera (Onodera Megumi) / Tally Onodera - System Operator. Voiced by Peggy O'Neal (US).
  • Monster Makers - Group of computer programmers/scientists who created the Digimon. Reunited by Yamaki.
    • Gorou Mizuno (水野 悟郎 Mizuno Gorō): Nickname "Shibumi". Continued on with the Digimon project after it was shut down in 1986. He later is able to help the kids while they are in the Digital World, as well as rejoining the Monster Makers in Shinjuku to help fight the D-Reaper. Voiced by Bob Glouberman (US).
    • Janyu Lee (李 鎮宇 Rī Janyū) / Janyu Wong: Nickname "Tao", Henry's father. He was voiced by Yoshiyuki Kaneko (Japan) and Jamieson Price (US).
    • Rob McCoy: Nickname "Dolphin", Alice's Grandfather, professor at Palo Alto University. Voiced by Tom Fahn (US).
    • Rai Aishuwarya: Nickname "Curly", professor at Miscatonic University. Voiced by Dorothy Elias-Fahn (US).
    • Babel: Real name unknown. Voiced by Neil Kaplan (US).
    • Daisy: Real or full name unknown. Voiced by Wendee Lee (US).
  • Man In Black - Unnamed Hypnos agent and field operative that is seen several times in the series. Voiced by R. Martin Klein.


  • The UK’s official Digimon comic (Panini) briefly delved into Yamaki’s history at one point, revealing that his father was a strict disciplinarian, who imparted to Yamaki his desire for order and control, which is what made Yamaki the man he is today – driving him to create the Hypnos program to monitor the actions of people all across the world and keep them in check and explaining his hatred of Digimon, which he views as disruptions to the natural order. However, while the UK comics are officially sanctioned, their story content is not approved by any Japanese creators, so this information does not strictly apply to the anime.
  • The unspoken irony of Yamaki’s situation is that it is possible that the Hypnos system actually created a window, a weak spot, between the Real World and the Digital World, allowing Digimon through in the first place. The series bible sees Chiaki Konaka toy around with this idea but it’s never fully confirmed as being truth in the finished series – though at one point, Yamaki does wonder if it could be the case.
  • The two programs used to activity fight anomalies, Yuggoth and Shaggi are both named after planets in the Cthulhu mythos, this can be attributed to Chiaki J. Konaka's interest in the works of H.P.Lovecraft. The bouts of insanity that Yamaki suffered could also be considered a call back to the Mythos and how the mere sight of the various cosmic entities of the Mythos is enough to drive anyone who sees them to insanity
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