The set-up: 15-year-old Kagome Higurashi is on her way to school one morning, when she hears a noise coming from the old well in the shrine her family tends to. She investigates and finds herself drawn into the well by a half-formed human/centipede monster. After escaping and climbing back out of the well, Kagome discovers she's no longer on the grounds of the shrine, but out in a vast forest; stranger still, a few yards away from her is an unconscious boy, pinned to a large tree by an arrow. The boy is the strangest of all, since he has long white hair and small, dog-like ears atop his head. Kagome is examining him when she's attacked by villagers. Villagers from Japan's Feudal Era, no less.

The villagers take her to see their miko, an old woman named Kaede. Kaede listens to Kagome's tale, that she is not from their land or even their time period, and is not sure what to believe. She tells Kagome that the boy was Inuyasha, a half-demon who was bound there 50 years ago by Kaede's older sister Kikyo; Kikyo was wounded in the battle, and died shortly after, requesting she be cremated with the object that she and Inuyasha had been fighting over: a jewel called the Shikon no Tama, said to increase the strength of demons. At this point, the centipede woman from before attacks the village; Kagome, in an effort to lead it away, runs back to the well she emerged from.

The half-demon Inuyasha awakens as she nears him, and taunts her, calling her Kikyo. Confused, Kagome is hit by the centipede woman, and injured on her side. A jewel drops out of her wound - the Shikon no Tama was inside her. The centipede woman eats it, and gains strength. Kagome ends up pinned to Inuyasha against the tree, and they argue over whether or not she is Kikyo and why she did this to him. Finally convincing him that her name is Ka-Go-Me, and she's not a 50-years-dead miko named Kikyo, Inuyasha tells her he can save them if she'll remove the enchanted arrow keeping him pinned to the tree; despite the urgings of the villagers, who have now caught up with her, Kagome chooses life over being crushed against a half demon who hates her, and frees Inuyasha. He makes short work of the demon that was attacking them, then tries to take the jewel himself. Kaede restrains him, and Inuyasha ends up coming along until it can be determined how Kagome came to this time from her own, whether or not she is actually the reincarnation of Kikyo, and what to do with the Shikon no Tama. Unfortunately, before any of those questions are answered, the jewel is shattered into hundreds of pieces and scattered over the land. Inuyasha and Kagome are recruited to find each piece before it falls into the wrong hands.