The Japanese word `` Kira '' is the equivalent of killer in English .
`` The series centers around Light 's subsequent attempts to use the Death Note to change the world into a utopian society without crime as a god-like vigilante named `` '' Kira '' '' ( ? ? , a Japanese transliteration of the English word killer ) and the subsequent efforts of an elite task-force of law enforcement officials , consisting of members of the Japanese police agency led by L , an enigmatic international detective , whose identity is anonymous , to apprehend him and end his reign of terror . ''