Tuxedo Mask is one of the most popular characters in Sailor Moon. He’s one of the few male characters with powers that rival the Sailor Guardians and plays a key role in almost every story arc. It’s also reiterated multiple times that Tuxedo Mask and Sailor Moon’s love for each other knows no bounds, and they would do anything to help each other. Fans may not know the Tuxedo Mask many are familiar with wasn’t always this benevolent. In fact, Tuxedo Mask is the least reliable out of Sailor Moon’s super-powered protagonists.
There were several instances throughout the anime and manga where Tuxedo Mask was one of Sailor Moon’s most dangerous enemies. Initially, this can be hard to believe for many long-time fans of the series. But there’s no denying that villains have taken advantage of Tuxedo Mask and used him to try to destroy the Sailor Scouts, especially Usagi. These instances were often when Tuxedo Mask wasn’t in control of his actions and was brainwashed into being a pawn in someone else’s schemes. And while Usagi and the other Scouts have forgiven him, it’s common that Mamoru will be just as dangerous against a force for good as he is against evil.
Tuxedo Mask Was Brainwashed Into Being Queen Beryl’s Loyal Servant
The ’90s Anime Had Mamoru Serve the Dark Kingdom
In Sailor Moon‘s first arc, Tuxedo Mask commits more evil acts than fans may remember. During the Dark Kingdom arc, the anime and manga have Mamoru brainwashed by Queen Beryl. This turns the once noble, enigmatic hero into a loyal servant of the Dark Kingdom. The original manga and Sailor Moon Crystal already depict Tuxedo Mask as a common jewel thief, but his possession takes his villainous streak to a whole new level.
Under Beryl’s possession, Tuxedo Mask directly confronts the Sailor Guardians. He comes to blows with them when they attempt to stop the Queen, with Sailor Moon being conflicted on whether to hurt Mamoru or not. In the original ’90s anime, Tuxedo Mask would even work alongside Shitennou and Kuznite to stop the Guardians. In the manga and Crystal versions of the story, Usagi is forced to use the Holy Sword to attack Tuxedo Mask. But even this ends up backfiring, as Usagi ends up stabbing herself with the blade. If Sailor Moon hadn’t survived the attack, there’s a likely chance that she could have died right then and there.

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No matter what version of the story fans experience, Usagi eventually finds a way to free Mamoru from the Dark Kingdom’s clutches. Using the power of the Silver Crystal, Usagi frees Tuxedo Mask from Beryl’s control and they both defeat Queen Metalia. However, that still doesn’t undo Mamoru’s actions from his time working with the Dark Kingdom. Subsequent arcs may not mention it again, but his contributions to Beryl’s cause only made things worse for the Sailor Guardians.
Tuxedo Mask would not openly acknowledge these mistakes in later arcs, either. Whenever he’s helping the Guardians, Mamoru doesn’t attempt to use any tactics to prevent his mind from being taken over again. The lack of foresight will come back to bite Tuxedo Mask several times, leaving him to harm his allies more than he assists them. His persistent love for Sailor Moon is the one thing that helps him fight back against these manipulative tactics, his dogged persistence strikingly similar to Prince Demande of the Black Moon arc.
Tuxedo Mask Continues to Cause Problems in the Black Moon Arc
Mamoru Gets Possessed Once Again, Working With Black Lady

If fans thought Tuxedo Mask getting manipulated would stop at the Dark Kingdom arc, then they were swiftly proven false. Mamoru once again falls under the spell of the next major antagonist faction, the Black Moon Clan. This time, Mamoru is mindwiped and manipulated by Black Lady, a corrupted version of his future daughter, Chibi-Usa. As Tuxedo Mask impedes the Sailor Guardians yet again, the effects of his second possession are even more disturbing than the first.
Under Queen Beryl, Tuxedo Mask simply believed she was his fated lover, and Sailor Moon was his true enemy. This role reversal makes Tuxedo Mask antagonistic against the Guardians, but his lingering feelings for Usagi still prevent him from hurting her too much. Black Lady’s possession of Tuxedo Mask reduces him to nothing more than a puppet she can use however she wants. In one of the most infamous scenes in the series, Black Lady kisses her future father and uses him as a tool to use against the Sailor Scouts. The fight between Black Lady, Tuxedo Mask, and the Sailor Guardians is still one of the best battles from the Black Moon arc, but the way it warps Mamoru’s free will is horrifying.

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In the fight against Black Lady, Tuxedo Mask does still show signs of rejecting her control over him. Just like in the Dark Kingdom arc, Tuxedo Mask’s love for Usagi is what helps snap him out of his brainwashing. Unfortunately, Mamoru’s meager resistance still doesn’t stop him from trying to take down the Guardians. Once he snaps out of the brainwashing, the damage has already been done. His actions still furthered Black Lady’s descent into darkness and helped the Black Moon Clan hold off the Sailor Guardians.
Sailor Moon’s Final Arc Reduces Tuxedo Mask to a Mindless Zombie
Sailor Galaxia Kills & Ressurects the Masked Hero to Use Against Sailor Moon

After the Black Moon arc, it seemed like Tuxedo Mask was finally getting more time to properly help the Sailor Guardians. In the Infinity arc, he helps keep Chibi-Usa alive by giving a part of his life energy to the young princess. While he didn’t strike the final blow against Pharoah 90, he and the other Sailor Guardians still pooled their energies into defeating the monster. He also helped in later battles against the Dead Moon Circus and Queen Nehelenia, even when he was ill.
However, the Stars Arc would see Tuxedo Mask be cruelly killed by the vicious Sailor Galaxia. The leader of Shadow Galactica then resurrects Tuxedo’s Mask, pitting him against Usagi and her allies once again. Initially, fans might get tired of Tuxedo Mask constantly getting brainwashed into serving the schemes of the villains. But this particular resurrection is even worse than the other two.

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On top of killing Tuxedo Mask, the forces of Shadow Galatica slaughters almost every other Sailor Guardian who isn’t Usagi. Not only does Sailor Moon need to deal with a brainwashed Tuxedo Mask for a third time, but she doesn’t even have any of her friends to help console her. The Stars Arc is famous for pushing Usagi to her absolute limits, and Galaxia forcing Tuxedo Mask to betray her yet again is the cherry on top.
This doesn’t mark the end of Tuxedo Mask’s story, though. Mamoru does start to snap out of the brainwashing, once his feelings for Usagi start to resurface. His realization that he’s been brainwashed again comes too little too late, however. Usagi is still forced to choose between usurping the entity Chaos or living a normal life with the rest of her friends. And amid all this drama, Mamoru is utterly helpless, only able to reconnect with Usagi once the battle against Shadow Galactica is finally over.

- Release Date
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March 7, 1992
- Directors
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Junichi Sato, Kunihiko Ikuhara
- Writers
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Sukehiro Tomita