In Japan's Warring States period, a half-demon boy named Inuyasha is sealed by the priestess Kikyo. Centuries later, Kagome, a modern-day schoolgirl, is transported back in time and accidentally breaks the seal, awakening Inuyasha. Just then, a centipede demon attacks and tears into Kagome's side—revealing the Sacred Jewel, the Shikon no Tama. The demon swallows it, but Inuyasha swiftly defeats it with a single blow.

With Kagome's ability to detect jewel shards and Inuyasha's power to fight demons, they're forced to team up to retrieve the scattered fragments. However, they quarrel, and Kagome returns to her time through the Bone-Eater's Well. Meanwhile, the demon Yura uses villagers to ambush Inuyasha. Injured but determined, he follows Kagome back to the modern world.