L Lawliet widely known by the letter L , is a fictional character in the manga and anime series Death Note by Tsugumi Ohba and Takeshi Obata. Considered the world's greatest detective, he lives in secrecy. During the story, he acts as the main antagonist to Light Yagami, otherwise known as the mass-murderer "Kira". However, his popularity as a character inspired the release of a spin-off live-action film L: Change the World and a novel adaption of said film where he is the main protagonist.