In ancient Japan, a miko [priestess] Kikyou dies protecting the Shikon no Tama [Jewel of the Four Souls], the magical jewel that is said to give immense power to Youkai [demons]. She seals the Hanyou [Half-Youkai], Inuyasha, who was trying to steal it. In the present, a girl who looks almost exactly like Kikyou, Higurashi Kagome falls into a well in her family's shrine and is transported to ancient Japan, 50 after Kikyou has died. The carries the Shikon no Tama within her body which a centipede Youkai steals. She must pull out Inuyasha's seal to prevent the Shikon no Tama from being absorbed by the centipede Youkai. But a few days later, while trying to kill another Youkai which tried to steal the Shikon no Tama, Kagome shatters the Shikon no Tama with her arrow. Now, she and Inuyasha must find the shards of the Shikon no Tama. In their journey, they meet Miroku, Shippo, and Sango, who join them in their journey.

However, in the middle, Kikyou gets revived by a sorceress and a mystery between Kikyou and Inuyasha is revealed. 50 years ago, a Youkai, Naraku, took the form of Inuyasha and betrayed Kikyou, causing Kikyou to hate Inuyasha. The same Naraku was the one who cursed Miroku's grandfather by putting an Air Void in his right hand. This gets passed down in Miroku's lineage. If he does not kill Naraku, he will be consumed by his own Air Void. Sango's family and village was destroyed by Naraku and her brother was taken. Now, Inuyasha, Kagome, Miroku, Sango, and Shippo must find Naraku and eliminate him.

This anime series is still running in Japan, I think. I have until episode 94 and the first movie.