The plot revolves around a case of mistaken identity between a pair of identical brothers. In the afterword, Jin Yong acknowledges that the story resembles some of the works of William Shakespeare. The protagonist, who refers to himself as "Gouzazhong", first appears as a young beggar roaming the streets of Kaifeng in search of his lost mother. He witnesses a fight between several jianghu figures and meets the Shi couple and members of the Snowy Mountain Sect. An accident causes him to be taken away by Xie Yanke, an eccentric martial artist, to his secluded home on Motian Cliff. Xie Yanke, who is frequently bothered by Gouzazhong, decides to teach him martial arts. Gouzazhong learns qi cultivation techniques under Xie Yanke's tutelage for six years, but is unaware that Xie actually harbours ill intentions and has been teaching him the wrong methods, in the hope that he will sustain internal wounds and eventually die. At the same time, the leader of the Changle Sect, Shi Zhongyu, mysteriously disappears. The greater part of the novel deals with the complications that arise as Gouzhazhong is mistaken for Shi Zhongyu, not only by members of the sect, by also by Shi Zhongyu's parents, the Shi couple, Shi Zhongyu's lover Ding Dang, and members of the Snowy Mountain Sect. Although the two bear a splitting resemblance, their characters cannot be more different: Gouzhazhong is simple, honest and clever, while Shi Zhongyu, the son of the Shi couple, has a bad reputation for being a lewd and sly womaniser. Gouzhazhong acquires consummate combat skills in the process. He is hounded by members of the Snowy Mountain Sect who mistake him for Shi Zhongyu, who molested Axiu, the granddaughter of the Snowy Mountain Sect's leader. He acquires Axiu as his girlfriend after various incidents, during which the misunderstandings are gradually resolved. The novel culminates in an episode when the leaders of various sects are coerced into visiting a secluded island by a pair of mysterious, highly skilled messengers to celebrate the Laba Festival. The story then leads to a surprising conclusion: revelations on the island and more revelations concerning Gouzhazhong's true parentage.
