Light Yagami obtains a "Death Note." He writes the name of an acquaintance, and the acquaintance dies. Later, in order to protect his father who is also a detective, Light, out of a sense of justice, kills criminals one after another by using the Death Note.

Light senses that he's being watched by someone. He suspects that L is behind this, and plans to take out the tailer and L together.

When Light receives a phone call from L, Light realizes that he is suspected of being Kira. Meanwhile, Ryuk proposes to give Light the "Shinigami Eye" in exchange for certain conditions.

Light believes that there is another Kira because the FBI agent who was after Light died without Light's intervention. Meanwhile, Light suspects that L has planted a surveillance camera in Light's room.

Misa confesses to Light that she has the Death Note and the Shinigami Eyes. Light tries to find out L's actual name using Misa's Shinigami Eyes.

Misa is detained on suspicion of being the second Kira, and she, unable to bear the interrogation by L, asks Rem to kill her. Meanwhile, Rem orders Light to save Misa, and Light visits L to clear his suspicions.

Unconvinced that Light is not Kira, L decides to put Light under 24-hour surveillance. In order to prove his innocence, Light offers to cooperate in Kira's arrest.

A man, Higuchi, arrested as the third Kira dies. L investigates the Death Note which Higuchi possessed, but with the fake rule written by Ryuk, Light and Misa are exonerated.

Light succeeds in writing L's real name in the Death Note, but L put a trick in the notebook. Light, trapped in a tough spot, decides to take action.

Light and his father head to the designated location with the Death Note in order to rescue Sayu, who has been captured by Himura.

After L's death, Light's father also loses his life. Light, determined to do whatever it takes to create an ideal world without crime, decides to eliminate Mello.