Mistress 9 is revealed to have been residing within Hotaru's body and awakens upon stealing Chibiusa's Heart Crystal, the Sailor Soldiers go to Mugen Academy to stop the Death Busters and save Chibiusa, Hotaru, & the world. Sailor Moon is the only one who is able to get in to the academy thanks to Mistress 9 and Pluto sacrifices her life to save Uranus and Neptune who are able to make it in the academy as well, the other Sailor Soldiers then place up a barrier to keep the enemy from destroying the city and the world. Mistress 9 then tricks Usagi into handing over the Holy Grail, allowing her to summon Pharaoh 90 to destroy the Earth. Hotaru awakens as Sailor Saturn, destroys Mistress 9, and intends to sacrifice herself to stop Pharaoh 90, but Usagi is able to activate her Super form to both destroy Pharaoh 90 and rescue Hotaru. Afterwards, Hotaru is reborn as a baby and returned to her father, now freed from the influence of the Death Busters. Uranus and Neptune then challenge Usagi to a fight to prove to them and everyone that she is the true Messiah and the future queen of Silver Millennium, after the fight they both acknowledge her as their queen and leave the city knowing their mission is now over and that it’s in safe hands. Right after Chibiusa receives a letter from her parents from the future wanting her to return home and she does but after returning to help the Sailor Soldiers and Tuxedo Mask defeat the last Daimon monster, Chibiusa decides to stay in the present a bit longer.