Rebel fighters pretend to be craftsmen, Zhang Luo smells a rat and decides to check things out, only to be pushed into the river by them. The craftsman studies the fragments from Zhang Xiaojing closely and comes to the conclusion that they are from bamboo sticks used to build the Heavenly Lantern Tower, and that Long Bo could fill them with stone grease and make the Lantern Tower a 50-metre explosive. If detonated, it would instantly destroy everything within a few kilometres.
蚍蜉们假扮工匠张洛发现异常，他想上前打听清楚，却被蚍蜉们推下河。晁分反复观察张小敬拿来的碎竹片，他断定这是用来建造太上玄元大灯楼的竹片，龙波可能会利用竹子装石脂，那样一来大灯楼就变成了一个高150尺的伏火雷，一旦引爆方圆数里就会被炸成平地。元载率右骁卫团团围住晁分家，还以伊斯的性命相威胁，逼张小敬束手就擒。檀棋拿着鼓袋混入乐班，顺利登上花萼相辉楼，却在这里遇到了严羽幻。龙波带李必参观大灯楼，李必看到蚍蜉们在往麒麟臂里装石脂，发誓要阻止他炸毁长安，龙波根本不把他放在眼里。伊斯被元载折磨得叫苦不迭，张小敬奋不顾身跳出来营救。
