Lin Rui, a veteran, is heavily in debt and struggling to make ends meet, unable to find work.

After failing another job interview, he met a mysterious middle-aged man who offered him a contract with a military security company. His life was forever changed by this contract. He became a contract worker active on battlefields around the world.

He travels the world, carrying out highly dangerous missions in hotspots. From an unknown battlefield fodder to a renowned king of mercenaries.