Duanmu Rong tells Gao Jianli that she has checked all the water in the City, and somehow there's no prison at all. Ge Nie is prisoned, and Tianming is furious with the Mohists. Xuenv immobilizes him and put him into the room next to Ge Nie's. Duanmu Rong gives the Mohists leaders her unique pills that can resist any prisons for four hours just in case. At the daybreak Duanmu Rong is suddenly reminded of a poison called One Thousand Nights, the poison that never attacks unless it's exposed to sunshine. The poison became gas and the whole City is paralysed. Tianming feels painful because of the gas, and Ge Nie tries to teach him to resist. Wei Zhuang and Qin's armies began their attack.
盖聂被软禁，天明要进去却被阻拦在外，天明十分生气，大闹着指责端木蓉几人，最终被雪女点穴安静了下来。高渐离发现机关城内可能潜伏着危险的敌人，然而中央水池经过检验竟无丝毫异样，令众人颇感蹊跷，机关城内加强了防守。另一方面，秦始皇等待墨家灭亡，而卫庄已下令准备行动，一场杀机浓厚的阴霾正向机关城席卷而来。
