During the 2nd Sino-Japanese War, orphan Lu Feng returns to Shanghai as a Communist undercover agent, tasked with infiltrating No. 76 Headquarters. There, he crosses paths with the mysterious Hua Xiang Yu and his childhood friend Huo Fei, both hiding secrets of their own. As they circle each other in a dangerous game of loyalty and deception, these hidden agents must decide what they truly stand for, risking everything to fight for a better future.

地产大亨王小虎（曾志伟饰）在大街上撞了一个捉鸡的老人，天上的热气球驾驶员李大春（夏雨饰）看见了这一幕，却并不知道那个老人就是自己的老丈人。大春打电话给老婆欢儿（梁咏琪饰）让她回家跟老丈人吃饭，被妻子断然拒绝。欢儿因为啤酒妹这份工作而被父亲赶出家门，一直心有怨气。 老丈人因为撞击脑部有血块，需要马上做手术。窝囊的大春鼓起勇气三番四次向王小虎要钱都被赶出来。 80后女孩糖糖（唐嫣饰）是小虎的情人，同时跟“钢琴家”乔邦（戚迹饰）恋爱。为了全国巡演乔邦跟高利贷借了30万，如今被高利贷追杀。为了替乔邦还债，糖糖自导自演了绑架案。 棒子老虎鸡，一物降一物，这个连环套到最后，到底谁被降住了呢？