When the criminal dies immediately following his experiment with the Death Note, Light is greatly surprised and quickly recognizes how devastating the power that has fallen into his hands could be.
High school student and prodigy Light Yagami stumbles upon the Death Note and-since he deplores the state of the world-tests the deadly notebook by writing a criminal's name in it. One day, Ryuk, bored by the shinigami lifestyle and interested in seeing how a human would use a Death Note, drops one into the human realm.
A shinigami, as a god of death, can kill any person-provided they see their victim's face and write their victim's name in a notebook called a Death Note.