When high school student Light Yagami finds a murder notebook called the "Death Note," able to kill any persons he recognizes by simply writing their names into it, Light begins mass murdering criminals with heart attacks in hopes to create a world free of evil and to eventually become its god. Light is soon visited by the Death Note's owner, a Shinigami named Ryuk, who allows Light to keep it but must stay near him. After it becomes apparent someone is killing a large number of people, Light anonymously receives the nickname "Kira." The Japanese National Police Agency, or "NPA," along with a mysterious detective known only as "L," decide to find and arrest him as a murderer. L realizes that Kira needs to know the faces of those he kills, causing a few Japanese investigators to stop aiding the search in fear of their lives. L later requests the FBI's help to investigate all NPA members involved in the Kira Case when he suspects one of them may be related to Kira. One FBI agent follows Soichiro Yagami, Light's father and one of Kira's investigators, and his family. Light discovers his tail, and uses the Death Note elaborately to learn the name of the agent.