In the world, there are various immortals disguised as human beings. The biggest difference between these immortals and humans is that each immortal has a special instrument to assist them in fulfilling their missions. Whenever new immortals take office or old ones retire, they will hand over or claim their instruments in the Arsenal. There are times when some old immortals, coveting the power, refuse to turn in the instruments; and some new immortals, being not familiar with their own identities and instruments when awakening, misuse them. Under these circumstances, someone has to take over their instruments with force and supervise the using of them. And this person is the protagonist of the story Lu Xifeng. However, he has his own secret...