Sailor Moon (美少女戦士セーラームーン Bishōjo Senshi Sērā Mūn^?, originally translated as Pretty Soldier Sailor Moon^[1] and later as Pretty Guardian Sailor Moon^[2][3]) is a Japanese shōjo manga series written and illustrated by Naoko Takeuchi. It was originally serialized in Nakayoshi from 1991 to 1997; the 52 individual chapters were published in 18 tankōbon volumes. The series follows the adventures of Usagi Tsukino as she transforms into the titular character to search for a princess and an artifact called the "Legendary Silver Crystal" (「幻の銀水晶」 Maboroshi no Ginzuishō^?, lit. "Phantom Silver Crystal"). During her journey, she leads a diverse group of comrades, the Sailor Soldiers (セーラー戦士 Sērā Senshi^?) — Sailor Guardians in later editions — as they battle against villains to prevent the theft of the Silver Crystal and the destruction of the Solar System.