Usagi and Mamoru had previously lived their lives deeply in love, as the Princess of the Moon and Prince of the Earth.

Although in the present they have once again managed to meet due to their strong attraction, the love between the two of them cannot be allowed.

Looking to find his true self, Mamoru has journeyed to London. Having given up on Mamoru, Usagi now decides to focus all her strength on regaining the dark-hearted Ami.

Meanwhile, a single senshi appears in front of Ami. (Sailor Mercury.) Stating, ""I will surely restore you,"" who could this senshi be? And a mysterious girl also happens to appear in front of Usagi, Rei, and Makoto at the same time.