In "Death Note," the theme of identity and self-discovery is primarily explored through the character of Light Yagami, the main protagonist who discovers the Death Note and takes on the persona of the vigilante Kira. As Light begins to use the Death Note to eliminate criminals, he grapples with questions of morality, power, and the true nature of justice. Throughout the series, Light's sense of self evolves as he becomes consumed by his alter ego, leading to a complex exploration of how one's identity can be shaped by external influences and internal motivations. Additionally, the character of L serves as a foil to Light, challenging his beliefs and forcing him to confront his own sense of identity and purpose. Through these characters and their interactions, "Death Note" delves into the complexities of identity and self-discovery in a gripping and thought-provoking manner.