Senior technician Lu Yan works around the clock for three days and three nights repairing equipment during a torrential downpour, only to have 600 yuan deducted from her wages by the newly appointed director, Liu Yue, for failing to clock in. She refuses to keep covering for the company for free and decides to follow the rules to the letter: without a time clock, she won't work. The new supervisor repeatedly makes mistakes while installing German equipment, and the machinery breaks down on the day of the chairman's ribbon-cutting ceremony. Liu Yue tries to cover things up by purchasing technical specifications and swapping samples, but substandard components ultimately cause a landmark construction project to collapse. Lu Yan saves the endangered building in 72 hours, exposes the kickback scandal, and eventually becomes the group's chief engineer. The world will never let sincerity go unrewarded. The top female technician always lets her skills speak for themselves.