Seven years ago, the whole Jiang family, which was famous for its strange and amazing medical skills, was massacred. Miss Jiang Chan, who only went out to collect medicine, luckily escaped. Among the corpses on the ground, she found the number one killer in the world. The token of organizing the Twelve Lisha Building. As the top assassins of Lisha Tower, the identities of the Twelve Lisha are hidden and elusive. No one except the owner of the building knows the identity and whereabouts of these twelve people. In order to find out the truth, Jiang Chan worked hard to practice the Jiang family's secret skill Mingyue Yin, and later joined Lisha Tower under the pseudonym Hua Fan. She found the list of those who had done missions in the Twelve Lisha Towers on the day the Jiang family was wiped out, and tried to verify it. In the end, there was only one name left on the list: Zheliu, the head of the Twelve Lisha Towers, and the only one who left the Lisha Tower alive. The former number one killer who retired.