He was portrayed by Tatsuya Fujiwara.
Lights is a a first-year law student at a university. At one point, he hacks into the government database and finds that the government secretly acknowledges that it is unable to prosecute many criminals. Light discovers the Death Note in an alley during a rainy night after encountering Takuo Shibuimaru in a club. Light uses the Death Note to kill Shibuimaru, though because he does not specify on the cause of death, Shibuimaru dies of a heart attack. After leaving the scene of the crime, he meets Ryuk, who admitts that he is going to let him keep and use the Death Note given he had left it behind on purpose because he was bored. Light eventually kills his girlfriend, Shiori Akino, and frames her death as a murder in order to join the Kira investigation team as a result of their sympathy.
He eventually gives the notebook to Kiyomi Takada. After Takada is caught, Light kills her to recover the Death Note, but it is taken by the investigation team. L states that he will test the 13-Day Rule, a fake Death Note rule designed to prove Light and Misa's innocence. Rem, knowing that L's actions will reveal Misa's identity as the 2nd Kira, writes both L's and Watari's names in the Death Note. Light then proceeds to write his father's, Soichiro's, name in the book, manipulating his father to return the confiscated Death Note.
However, once he confronts his father, he finds that he is still alive. The investigation team members, including L, reveal themselves. Having already written his own name in the Death Note, thus negating Rem's actions, L tells Light that he had just written in a fake note.Light tries to write on a hidden piece of Death Note, but is shot by Matsuda, an investigation team member. Light tells Ryuk to write the team's names, promising to show him many interesting things, and begins to laugh. He stops, however, when Ryuk shows him that he had written just one name: Light's. Light tries to stop Ryuk, but merely passes right through him. As Light begins to succumb to the effects of the Death Note, Ryuk takes this opportunity to reveal to him that humans that have used the Death Note are barred from entering either Heaven or Hell, instead spending eternity in nothingness. Light dies in his father's arms, begging him to believe that he acted as Kira to put the justice, which Soichiro had taught him since his childhood, into practice.