Dark Kingdom
In the first arc, the group battles the Dark Kingdom, whose members attempt to find the Silver Crystal and free an imprisoned, evil entity called Queen Metaria. Usagi and her team discover that in their previous lives they were members of the ancient Moon Kingdom in a period of time called the Silver Millennium. The Dark Kingdom waged war against them, resulting in the destruction of the Moon Kingdom. Its ruler Queen Serenity sent her daughter Princess Serenity, reincarnated as Usagi, along with her protectors the Sailor Guardians, their feline advisers Luna and Artemis, and the princess' true love Prince Endymion, who in turn was reborn as Mamoru.