"Jujutsu Kaisen" is set in a world where cursed energy, derived from negative emotions, manifests as dangerous supernatural entities known as curses. These curses threaten humanity, and only jujutsu sorcerers, individuals trained to harness cursed energy, can combat them. The story centers on Yuji Itadori, a high school student with exceptional physical abilities but no knowledge of the supernatural. His life changes drastically when he encounters a cursed object, a decaying finger belonging to Sukuna, a powerful and malevolent curse known as the King of Curses. To protect his friends from a curse drawn to the finger, Yuji consumes it, becoming Sukuna's vessel. Despite this, Yuji retains control over his body, though Sukuna occasionally emerges to wreak havoc.

Recognizing Yuji's potential, Satoru Gojo, a powerful jujutsu sorcerer, enrolls him in Tokyo Jujutsu High, a school dedicated to training sorcerers. Yuji joins fellow students Megumi Fushiguro, a reserved and skilled sorcerer specializing in summoning shikigami, and Nobara Kugisaki, a confident and headstrong fighter who uses a hammer and nails imbued with cursed energy. Together, they undertake missions to exorcise curses and protect humanity. The narrative explores their growth as sorcerers, their battles against increasingly dangerous curses, and the moral complexities of their roles.

The overarching plot involves the conflict between jujutsu sorcerers and curses, as well as internal strife within the jujutsu world. Sukuna's presence within Yuji poses a constant threat, as his immense power could destabilize the balance between humans and curses. Meanwhile, a group of rogue sorcerers and curses, led by the enigmatic Mahito, seeks to disrupt the status quo, often clashing with Yuji and his allies. Themes of sacrifice, duty, and the nature of humanity are woven into the narrative, as characters grapple with the consequences of their actions and the blurred lines between good and evil.

The series balances intense action sequences with character-driven moments, delving into the backstories and motivations of its cast. Satoru Gojo, a mentor figure, stands out as one of the most powerful sorcerers, often serving as a protector and guide. Other key characters include Toge Inumaki, who communicates through cursed speech, and Maki Zenin, a physically adept sorcerer from a prestigious but oppressive family. The interplay between these characters and their development adds depth to the story, making "Jujutsu Kaisen" a compelling exploration of its dark and intricate world.