Golgo 13 - The Professional

 ゴルゴ１３

Golgo 13 is the codename for the world's most deadly hit men, a man whose identity is unknown and sought after. After a routine hit on the son of a wealthy oil tycoon and a shadowy figure known as Dr. Z who controls a big number of mafia bosses; Golgo 13 finds himself prey to the CIA and the U.S. Army, whom Dawson has personally hired to kill his son's assassin. As days pass by, Dawson slowly loses his sanity as he continues to plot every attempt to kill Golgo 13 even without caring about who hired the assassin to kill his son, and even using his own family.