A modern disaster prevention expert time-travels to ancient times, opening his eyes only to find himself kneeling at the execution grounds awaiting decapitation! Facing a capital crime, he cleverly exposes a miscarriage of justice, just as a city-destroying crisis strikes with the breaching of the river dikes. Giving up on fleeing for survival, Shen Yanchuan uses his rescue expertise, modifying equipment and organizing disaster victims, going head-to-head against corrupt officials, greedy merchants, and bandit conspiracies. Amidst the howling winds and torrential rain, with a mortal body he shoulders the heavy burden of guarding the city, resolving multiple crises of floods, poisoning, and merchant chaos while gathering evidence of crimes to confront the dark forces behind the scenes, protecting thousands of ordinary people amidst the chaos and disasters of the troubled times.