Codename Planet Boy
Name Yuusei
Gender Male
Family Shonen
Occupation Warrior
Status Active
Creator Simon Kirby
First Appearance MSN Groups, 2005
Yuusei Shonen no Kyohaku Sekkou (Planet Boy of The Space Patrol) is an open source character created by SimonKirby and released via MSN Groups in 2005. Loosely based on early 60s Japanese cartoons (Astroboy, Gigantor, Prince Planet etc), Yuusei Shonen follows the story of a young extra-terrestrial warrior defending the Earth from alien menaces.


A vast shadow has fallen over the planet Earth in the 'far-off future' of 2010. The shape-shifting Zygons, one of the most hated species in entire the galaxy, have begun infiltrating human society via its smallest and most defenseless members: young children.

While this secret invasion goes unnoticed by most of humanity, The Supreme Galactic Council has sent its greatest warrior to deal with the Zygon infestation. Armed with the power and technology of a thousand worlds, Yuusei Shonen undertakes the most important mission of his career - to protect an entire planet from the most dangerous creatures in the universe.

His orders are simple: hunt down and exterminate the Zygons before they can breed. Failure is not an option; if the aliens manage to propagate, The Galactic Council will be forced to destroy the entire solar system.

The fate of the Earth is literally in Yuusei's hands - but how can he even hope to succeed against such a devious and dangerous enemy?


Yuusei Shonen is a Spock-like alien boy sent to study humanity and decide if the planet Earth should be admitted to the Galactic Union. His exact point of origin is unclear, but he is said to hail from somewhere beyond the Xoltarian Nebula.

After arriving on Earth, Yuusei assumes a secret identity as a Tokyo schoolboy, using his telepathic powers to learn the Japanese language in a matter of days. Due to the Sun's relative brightness compared to his home world, Yuusei is forced to wear an infra-red visor in his civilian identity (which can be adjusted to perceive any range of the electromagnetic spectrum).

During his first week in Miyamae-Ku, he makes the acquaintance of two local children, Hiro Kanangawa and Keiko Masuda. Despite some initial trust issues, the three quickly become allies when their classmates begin to mysteriously disappear. Being unusually perceptive for her age, Keiko has already deduced the existence of aliens within their school and believes that they are replacing her friends with "doppelgangers".

The aliens are revealed to be shape-shifting creatures known as Zygons, one of the most feared species in the galaxy. Space-borne parasites from the outer fringes of the cosmos, they have been known to obliterate entire systems in their wake, reproducing like a viral infection within native populations.

Yuusei is forced to expose his dual identity when a group of Zygons launch a surprise attack. After successfully fending off the invaders, Keiko explains that she already knew that Yuusei wasn't quite human, but that she and Hiro will keep his secret if he's willing to trust them. Yuusei agrees, and they join forces to battle the predators.

In the meantime, The Galactic Council has targeted downtown Tokyo, believing that it would be better to destroy the entire city than allow the Zygon contamination to continue spreading across the galaxy. Against Yuusei's recommendations, Japan is suddenly swamped with giant lizards, killer robots and slavering monstrocities, each one worse than the last.

Worse still, the Zygons' Brood Queen has continued to breed, filling Miyamae-Ku with infected children. Once they assume human form, Zygons can only be identified by a close physical examination. At times, Yuusei isn't even sure whether Keiko has been contaminated, the illusion is so convincing.

After a long struggle, Yuusei manages to track down and destroy the Zygons' lair, though he suspects that the Brood Queen escaped further underground. The Galactic Council calls off its attack, but orders Yuusei to stay behind until the Queen's extermination can be verified.

With the first phase of his mission accomplished, Yuusei undertakes to learn as much about human civilization as possible , even allowing himself to experience unfamiliar emotions (such as love and compassion). All the same, he cannot afford to drop his guard too far - if his suspicions are correct, the Brood Queen is merely hibernating, and a new outbreak of the Zygon Plague could erupt at any time...

See also


Yuusei Shonen is an open source character specifically created for use by anyone. Feel free to use it any way you wish; author citations are not necessary.

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