A teacher on a Greek island becomes involved in bizarre mind-games with the island’s magus (magician) and a beautiful young woman.

Emiya Shirou is a young magus who attends Homurahara Academy in Fuyuki City. One day after cleaning the Archery Dojo in his school, he catches a glimpse of a fight between superhuman beings, and he gets involved in the Holy Grail War, a ritual where magi called Masters fight each other with their Servants to win the Holy Grail. Shirou joins the battle to stop an evildoer from winning the Grail and to save innocent people, but everything goes wrong when a mysterious “Shadow” begins to indiscriminately kill people in Fuyuki…

Asta and Yuno were abandoned together at the same church, and have been inseparable since. As children, they promised that they would compete against each other to see who would become the next Emperor Magus. However, as they grew up, some differences between them became plain. Yuno was a genius with magic, with amazing power and control, while Asta could not use magic at all, and tried to make up for his lack by training physically. When they received their Grimoires at age 15, Yuno got a spectacular book with a four-leaf clover (most people receive a three-leaf-clover), while Asta received nothing at all. However, when Yuno was threatened, the truth about Asta’s power was revealed, he received a five-leaf clover Grimoire, a “black clover”! Now the two friends are heading out in the world, both seeking the same goal!