Seventeen-year-old fighting genius Ji Yunshen was lured into an underground boxing match by Fang Yanqiu. He was framed for injuring others and was forced to join the killer organization "The Firm" and became a cold-blooded killer. In the organization, he knew and fell in love with the dispatcher Lin Moyu, but this relationship violated the iron laws of the organization. Lin Moyu was designed to be killed, and Ji Yunshen fell into extreme pain. After that, the new dispatcher Azhe broke into his life, and the two warmed each other and depended on each other. During the mission, he met Zhongshan, a Jianghu man who insisted on the bottom line. In order to save his family and Ji Yunshen, Zhongshan chose to commit suicide. Ji Yun was deeply touched and began to reflect on the road of killing. In the end, Ji Yunshen avenged Lin Moyu and liquidated his enemies, completely broke with the "firm" and got rid of his identity as a killer. He took Azhe and the cat Snowball overseas and became an overseas security guard, completing his redemption by protecting others.
Ji Yunshen, with his longing for Lin Moyu, transformed from a killer of darkness into a guardian of light, and found his way back in life in the endless wandering.
