In a world plagued by brutal murders, petty crimes, and senseless violence, the realm of the Shinigami exists as a monotonous gambling haven. Light Yagami, a brilliant 17-year-old Japanese student, and Ryuk, a bored Shinigami, both perceive flaws in their respective worlds. Seeking amusement, Ryuk drops his Death Note into the human world, where Light discovers it. Although Light initially dismisses the notebook's first rule—that any human whose name is written in it will die—as absurd, he cannot resist the temptation. He writes the name of a criminal, successfully causing that person's death.
Awed by this immense power, Light adopts the alias Kira and launches a crusade to eradicate all criminals in the name of justice. His actions attract the attention of L, a meticulous and brilliant detective who begins the hunt for Kira. As Light's intellect rivals L's, the conflict evolves into a deadly battle of wits where the only possible outcome is the death of one of them.