Yuji Itadori, a high school student with superhuman abilities, encounters a sorcerer named Megumi Fushiguro who informs him of a cursed talisman located somewhere in his school. Later that night, Yuji’s friends, all part of an Occult club based in the school, unknowingly unseal the very cursed talisman Megumi had warned about.
The cursed item, a rotten finger, attracts evil curses to the school. In order to save his friends, Yuji swallows the finger. This transforms him into a host for the demon, Ryomen Sukuna, an ancient powerful curse that wreaked havoc on the world during his reign.
Yuji momentarily turns into Sukuna and faces Satoru Gojo who proclaims himself the strongest sorcerer and swiftly mops the floor with Sukuna. Gojo realizes that if Yuji manages to eat the remaining fingers before dying, they can destroy the talismans and thus, Sukuna’s spiritual form, in one fell swoop. He makes a difficult proposal to our hero — Itadori can either die at once or collect the remaining cursed fingers of Sukuna and then die.
Yuji agrees and becomes a sorcerer himself. During his stay at the school, he makes two friends – Megumi and Nobara. They eventually become a team and go on missions together. On one such mission, they encounter a special grade curse. They fail to measure up to it and decide to flee.
Yuji eventually stays back and turns into Sukuna so he can exorcise the special grade curse. Sukuna makes short work of the enemy, then heads to where Megumi is. The two initiate a battle which culminates in Sukuna ripping Yuji’s heart out. Yuji seemingly dies and takes Sukuna’s temporal form with him.
Yuji, however, wrestles with the curse and returns to the world of the living. Only Gojo and a select few know that Yuji is still alive. The former places the latter under the guidance of Kento Nanami, a former salaryman. During the period when the rest of the world does not know about Yuji being alive, he befriends Junpei, a boy who desires power in any shape or form to escape the bullies who torment him in school.
They come into conflict when Junpei’s mother dies and he tries to seek revenge. Mahito, a special grade curse that resembles a human, kills Junpei and instantly detects Yuji as the host of Sukuna. They have a fight where Yuji surprisingly holds his own. Nanami joins our hero and is able to overwhelm Mahito who flees the scene through the sewers.
Itadori, now having faced off against a special grade curse with his own strength this time, makes his way to the location where the other students are participating in an exchange event between two prefectural schools. He reveals his resurrection at this event but does not get the ovation he was expecting.
He forms a brotherly bond with Aoi Todo, an eccentric third year at Kyoto Jujutsu High School. Both the schools have a competition where they test their skills against each other. The event is short-lived as it is invaded by Hanami, a nature-worshipping special grade curse, and Mahito. The students and staff present at the school manage to repel the invasion. However, Mahito succeeds in stealing some artifacts from the school’s storage facility.
Later, Yuji and Nobara are sent on a mission where they come across two Death Paintings, human brothers who have both curse and human blood. Yuji and Nobara manage to kill them while Megumi exorcises another special grade curse. They are nominated for first grade sorcerer status due to their achievements. This is where the first season finale concludes.