The Outer Four

The Outer Senshi in the anime

Soldiers of the Outer Solar System is the official name given to the group of Sailor Senshi who defend the solar system from external threats: Saturn, Uranus, Neptune, and Pluto. They are traditionally refered to in the Western fandom as "Outer Senshi" for brevity's sake.


From the distant past, the Outer Sailor Senshi were given the task of protecting the Silver Millennium from enemies who intrude from outside the solar system. On Earth, Sailor Uranus and Sailor Neptune become, respectively, Haruka Tenou and Michiru Kaioh, partners and lovers a year older than the Inner Senshi. They work together for some time, only later joined by Setsuna Meioh (Sailor Pluto), a college student, and by Hotaru Tomoe (Sailor Saturn), a much younger girl (whose age varies due to rebirth and accelerated growth).

Though the Outer Senshi appear charming and personable in their civilian forms, their exact relationship to the original Sailor Team as senshi varies between adaptations. Initially, the two teams usually have a mutual and equal aversion to each other, with Usagi, Mamoru or Setsuna acting as mediators. Demonstrating extreme dedication to their roles as soldiers, the Outer Senshi can be aloof and ambivalent if they think conflicts will arise from attempted co-operation or as a mishandled way of protecting others, though they admittedly have no illusions of heroism in making ruthless choices. In all versions of the story, the question of how to handle the potentially destructive Sailor Saturn formed the largest conflict of interest between both groups. By the end of the arc more is learned of the Outer Senshi's past history in the Silver Millenium and the two teams mutually accept each other.

In the first anime, the Outer Senshi were portrayed as much more openly aggressive and prideful, disdaining the offer of help because of perceived weakness in Usagi's group. Their conflicts of interests continued all the way till the end of the season. Even later on they generally acted alone or in tandem, sometimes meshing poorly with the other team's pursuits. They also seemed to lack the closer friendship to Usagi's group implied in other versions of the story. Their exact role in the past is also left more ambiguous.

Each of the Outer Senshi fight with a special weapon; Uranus, Neptune, and Pluto bear the three Talismans (whose origins vary per adaptation), while Sailor Saturn carries the Silence Glaive. Early references to the Outer Senshi being explicitly stronger at their introduction are inconsistent among later adaptations, and the several power-ups that occur later in the story among all the senshi render the question moot.


  • As the series progress, they also seem to develop mild psychic abilities, able to sense and foretell impending dangers through nature and visions, which may fit in with their themed powers of destruction (earthquakes, tsunamis, time, death).
  • The apparent gap in maturity of the Outer Senshi is exaggerated in the first anime, leading to the common but incorrect fan belief Haruka (despite depicted as able to drive) or Michiru are significantly older than the rest of the cast.
  • The first anime's "Alien Tree" filler arc predates the debut of the Outer Senshi. Thus while presumably an 'external threat', no in-universe explanation has ever been provided as to the lack of their appearance in it.
  • Unlike the manga, the Outer Senshi's only appearance in the first anime's fourth arc is within a special side-story episode; while the Outer Senshi do appear in the SuperS movie, the movies are treated as out-of-canon. Its origin as a manga story highlights discrepancies between adaptations. For example, Pluto's presumably recent death is not apparent or mentioned (as she died and was reborn much earlier in the manga at this point) and the Outer Senshi show no aversion at all to working with the Inner Senshi, mirroring their original relationship from the manga.
  • The Outer Senshi's "Super Form" transformations are never shown in the anime. However, their forms only appear in the Stars arc of the anime when they power up because of baby Hotaru’s power.
  • During their transformations in the anime, Sailors Neptune, Uranus and Pluto are all shown with makeup. This may be a reference to the fact that some cultures believe that makeup is only for mature girls; the Outer Senshi are usually depicted as more "grown-up" and have different beliefs similar to an adult's, thus makeup is added to enforce that idea.