In "Death Note," the theme of the corrupting influence of ambition is depicted through the character of Light Yagami. Initially, Light's ambition to rid the world of evil by using the Death Note seems noble, but as he becomes more power-hungry and obsessed with becoming a god-like figure, his morals and values become increasingly corrupted. His ambition leads him to commit heinous acts and ultimately leads to his downfall, illustrating how unchecked ambition can have destructive consequences.