Usagi Tsukino is an average and clumsy student who consistently struggles to do well on her tests. However, her life takes an exciting turn after she comes to the rescue of a cat with a crescent moon symbol on its forehead. Luna, the cat, informs Usagi that their encounter was not coincidental and that she is meant to become Sailor Moon. As a protector of the planet, she receives a special brooch that enables her to transform and defeat the energy-stealing monsters of Queen Beryl from the Dark Kingdom. Apart from learning to navigate her powers and battling evil, Usagi must also locate the lost princess of the Moon Kingdom, the other Sailor Guardians, and the powerful Silver Crystal to prevent the planet from destruction.