As Sailor Moon and her fellow Sailor Guardians safeguard Earth, ominous prophecies trouble Sailor Mars while the arrival of Sailor Neptune and Sailor Uranus foretells a looming conflict. The new guardians pursue three Talismans concealed within Pure Heart Crystals, essential components of The Holy Grail—a potent artifact of immense power. Their mission to harness the Grail's abilities for planetary salvation clashes with the malevolent ambitions of the Death Busters, a sinister faction intent on seizing its power. The ethical dilemma unfolds as extracting a Talisman results in the host's demise, a sacrifice deemed necessary by Uranus and Neptune but vehemently opposed by Sailor Moon's team. The looming question persists: is any sacrifice justifiable if it means preserving humanity's existence?