It loosely adapts the Underground Empire of Yomi arc, having went into production at the time the arc started in Weekly Shonen Magazine. It also folds in some elements of the Assassins and The Mythos Cyborgs arcs.
Though the proper English title is "Monster Wars", Toei's international catalog gives its title as "Cyborg 009: Underground Duel".
The 00 CyborgsEdit
Some time has passed since the Black Ghost organization was believed defeated, but ultra sonic-wave emitting dinosaurs have wreaked havoc across the world.
009 is called back into action, after reuniting with 004. He sets to work on gathering the other cyborgs, along with 007, who pretends to be a football at 002's football game. When 009 meets with 003 after a ballet recital, she is reluctant to return to her life as a cyborg, and he is about to let her be, when she later meets up with him on the plane back.
The two are driving back to Dr. Gilmore's research center when they get into a car accident with another out-of-control car, and find a young woman inside. They take her back to the lab, and the cyborgs make the decision to go after Black Ghost, riding off in their new ship "The Dolphin". They soon find that the girl, Helena, has stowed away with them, insisting that she has to go with them as Black Ghost had killed her parents.
During the travel, unusual events occur, such as jellyfish that try to drain the power from the ship, along with the team having to fight spy stingrays and other threats. The ship's defense against the ultra-sonic waves is also broken down. 009 realizes that they had to have been sent by Black Ghost.
The team make their way to Black Ghost's base, housed in another realm located within an undersea cave. As they enter the caverns, Black Ghost sends out the 0011 twins to battle the team, and their "0010" is already there. While the other team members are unable to defeat the 0011 brothers, 009 tricks them into colliding with each other, resulting in their deaths.
Helena is soon shown to be ensnared by an underground plant and is rescued by 009, but with all the suspicious events that have occurred, along with the presence of a "spy cyborg 0010", 009 angrily deduces that she's an enemy and was responsible for the events. Helena confirms his suspicions, revealing herself to be Cyborg 0010 and fights against him, but is nearly swallowed up in a chasm. 009 shows her mercy and rescues her, but is still disgusted by her betrayal. Helena runs off in tears.
As the rest of the team remark on the betrayal while the Dolphin continues to drill through the underground world, 009 silently thinks about Helena. Elsewhere, Helena cries in despair over her situation in having to be his enemy.
The team make their way towards the Black Ghost's Parthenon-esque temple in the Dolphin, but quickly evacuate as an ultra-sonic-wave emitting robot dinosaur disintegrates it. 009 makes the decision to enter the dinosaur robot through its mouth and destroy it from the inside-out, causing it to go haywire and explode. 009 is believed dead by the rest of the team, who find themselves caught in an electromagnetic trap and by gun-toting Black Ghost soldiers.
009 lies unconscious at the bottom of the ocean, with Helena finding him and bringing him to safety. She leaves him behind, leaving her necklace with him. 009 rouses, finding the necklace.
In the Black Ghost temple, the leader (a large stone bird-like statue) is informed of the 00 cyborgs' capture, but reveals that it knows of Helena/0010's rescue of 009. She is nearly killed by a laser from its finger, as one suspicious blue-suited Black Ghost soldier rescues her, revealing himself to be 009 in disguise.
009 learns that the statue is the same Black Ghost leader from the previous battle (and was the brain in the machine), and sees that his friends are imprisoned in a cell of electromagnetic waves. He is made to do battle against the Black Ghost robot Achilles, who proves to be a challenge until Helena tells him to shoot its heels, causing it to fall to pieces.
Helena is shot by the statue's laser for her betrayal of Black Ghost, and subsequently fired upon multiple times by the soldiers' guns, but persists weakly in making her way to the cell to free the other cyborgs and uses her laser ring to kill a soldier standing in her way.
Upon their release, the 00 cyborgs do battle against the soldiers, before 003 and 009 remember Helena's predicament. The Black Ghost leader has vanished, and taunts the cyborgs on how the base is set to explode. A dying Helena informs 009 to hurry towards an escape rocket, and bids him farewell. A tearful 009 is forced to leave her corpse behind, as lava starts to flood into the base.
The 00 cyborgs are teleported into the rocket by 001, and make their way out of the temple and underground world at the last minute, narrowly avoiding an explosion of lava and rocks. They stand out on the shore, mourning Helena's death as 009 holds her necklace, musing that she had helped them defeat Black Ghost.
- 009: Hiroyuki Ōta
- 001: Kyoko Toriyama
- 002: Ryō Ishihara
- 003: Judy Ongg
- 004: Hiroshi Ōtake
- 005: Hiroshi Masuoka
- 006: Arihiro Fujimura
- 007: Machiko Soga
- 008: Kenji Utsumi
- Professor Gilmore: Jōji Yanami
- Helena: Etsuko Ichihara
The actors for 0011+ and 0011- were never credited, leaving their identities unknown.
- During one scene, the Rainbow Sentai pass by the Dolphin and wave at the 00 Cyborgs. Rainbow Sentai Robin was the predecessor of the 009 concept which was published in a manga in 1963 and a TV show came out in 1966. Many see this as the team giving 009 and his friends their blessing as their successors or a just a simple cameo.
Changes in the adaptationEdit
- During the sequence of the team reuniting, there is no individual scene given for 008 and he simply shows up with the rest at the meeting with Gilmore. This is due to the fact that the original Yomi arc contained a sequence and subplot where 008 is mutilated and left for dead, which would have been too dark for younger audiences.
- The "Helena" character in the film is an amalgam of the Mythos cyborg Helena and the Pu'Awak princess Helen, due to the latter effectively being a recycling of the former's design. Helena is also stated to be "Cyborg 0010". In the manga and 2001 anime, this number is meant to correspond to the two villainous twin cyborgs sent by the Black Ghost organization to attack the team.
- However, the twins do appear in the form of "Cyborg 0011+" and "Cyborg 0011-", although they are significantly altered to be two solid-colored humanoid beings with lightning bolt-styled hair. One brother is colored blue and the other is colored orange, although they can also change to yellow and pink when utilizing their electric abilities. As in their original appearance, Joe tricks the two into coming into contact and they electrocute each other to death, though their death sequence is significantly toned down.