When the outlaws of Liangshan Marsh attack Daming Prefecture to rescue Lu Junyi and Shi Xiu, Grand Secretary Liang Shijie, the governor of Daming, seeks help from the Imperial Tutor Cai Jing, his father-in-law, in the Song imperial capital Dongjing. Xuan Zan, who is under Cai, recommends his friend Guan Sheng, a military inspector in Pudong County, as cut out for the job. With the assent of Cao, Xuan rushes to Pudong to summon Guan. Guan comes with his friend Hao Siwen to the imperial court, where he is tasked with saving Daming and the latter appointed his lieutenant together with Xuan Zan.