Sailor strážkyne si v pokoji nažívajú a užívajú si mier, pričom boj s Čiernym Mesiacom je už iba spomienka. V správach však nečakane informujú verejnosť o objavení sa netvora v parku, neďaleko akadémie Mugen, ktorú navštevujú aj výnimočne nadaný pretekár Haruka Tenoh a nadaná huslistka Michiru Kaioh...

Zatiaľ čo je Chibi-Usa v zábavnom parku s Mamo-chanom, Sailor strážkyne neďaleko vyšetrujú akadémiu Mugen. Tá však má ochranku a dnu je schopná cez svoje transformačné pero dostať sa iba Usagi. Nepriateľ však chystá ďalší krok, a okrem iného sa tam pripletie aj Chibi-Usa a záhadné dievča, ktoré cestou stretne...

Usagi a dievčatá diskutujú o dvoch záhadných postavách, ktoré videli a vyzerajú ako Sailor strážkyne. Luna a Artemis ich varujú, aby boli opatrné, nakoľko si stále nie sú istí, či sú nepriateľmi, alebo spojencami...

V akadémii Mugen sa očakávajú dve veľké udalosti - husľový recitál Michiru Kaioh a koncert Mimi Hanyu. Medzičasom Chibi-Usa navštívi Hotaru a dozvedá sa niektoré temné skutočnosti...

Now that they have arrived at the ruined castle of Crystal Tokyo, Sailor Moon, Sailor Venus, Luna, Artemis, and Tuxedo Mask are all surprised to meet a tall young man who bears a strikingly close and unmistakable resemblance to Tuxedo Mask and who reveals himself as the strong-willed King of Crystal Tokyo, and Tuxedo Mask's own future self.

Sailor Moon has been taken captive by the envious Prince Demande, leaving Tuxedo Mask deeply worried about her safety. A distraught Chibi-Usa blames herself for all that has happened since she had secretly taken the mighty Silver Crystal of the future. But will she be able to do something to reverse all of the damage she has unwittingly done?

Chibi-Usa has mysteriously disappeared, which leaves Sailor Pluto, Tuxedo Mask and King Endymion all desperately worried, as she does not have her time key. Meanwhile, Tuxedo Mask is also on a quest to find and save Sailor Moon from the clutches of the Prince Demande, and begs her to lend him and everyone her strength. Meanwhile, Sailor Pluto is gravely concerned about a brewing storm that could rip a hole in the very fabric of space and time itself.

Now under the full control of Wiseman himself, Chibi-Usa has become the Death Phantom's most loyal minion and malevolent Queen of Darkness: Black Lady. Will Sailor Moon and her five dearest companions be able to release Chibi-Usa from the immensely strong negative energy that controls her, or will the past and future both fall to the point of nonexistence at the hands of its own princess and future queen?

With a vindictively evil adult Chibi-Usa now on the side of the Black Moon, the five Sailor Soldiers' are determined to save her. Sailor Moon is ready give up the supremely powerful Silver Crystal of the past, and even her own life, to have the real Chibi-Usa return. But Prince Demande has other plans in store for all that may foil even Wiseman's own plans of world annihilation.

With the supremely powerful Silver Crystals of the past and future in Prince Demande's hands, all is close to the point of annihilation. However, Sailor Pluto may have to pay the ultimate price to create a window of opportunity to allow Sailor Moon and the others to stop Death Phantom, and save both the past and future.

The final showdown between the true self of Wiseman and the newly formed six Sailor Senshi of the White Moon commences. Sailor Chibi Moon is ready to fight alongside Sailor Moon and save her homeland. But will their combined strength be enough to save both the past and the future?