The story of Inuyasha starts out on Higurashi Kagome's (a seemingly normal Japanese schoogirl) fifteenth birthday. On that day Kagome goes into the old dry well house near her house and is pulled down into it by a huge centipede demon. The demon departes and when Kagome emerges she finds herself in another world altogether, that world is in fact the Sengoku Jidai (the warring states period of ancient Japan). In that world Kagome frees the hanyou (half-demon) Inuyasha who was sealed into an eternal sleep, by a miko named Kikyou (who Kagome is a reincarnate of) and realizes that she is the carrier of the Shikon no Tama, a jewel that increases a demon's power. However, many demons and humans are searching for the Shikon no Tama and one of them, a crow demon manages to get its claws on it and fly away with it. In an effort to stop it Kagome shoots it with a magical arrow and, unfortunatly the arrow not only hits the crow demon, but the Shikon no Tama as well, shattering it into an unknown number of pieces.

Now Kagome and Inuyasha have to join forces to collect all shards and stop them from getting into the hands of demons or humans who would use the power for evil ends. So, since Inuyasha was and is desperatly seeking the Shikon no Tama to become a full demon and Kagome has the mysterious power to sense the shards, they are forced to join forces and search for the shards together.