During the age of the Silver Millennium, the Inner Senshi were the guardians of Princess Serenity. They were also the princesses of their respective planets, but lived on the Moon at times. When Queen Metaria and the Dark Kingdom invaded the Moon Kingdom, the four were killed while trying to protect their princess. After Queen Serenity sealed away Metallia, she used the power of the Silver Crystal to send the Inner Senshi, Princess Serenity, and Prince Endymion to the future to be reborn on Earth to live happy lives. time.