Gu Chuan is publicly laid off by Beichen Cold Chain, leaving them with one remark: "Tomorrow at nine in the morning, you'll beg me to come back." The next day, the Qingluan system that supports the city's entire cold chain network collapses completely. It turns out that the dismissed employee was the system's chief architect all along. After returning, Gu Chuan not only reclaims the achievements that others have falsely claimed as their own for seven years, but also uncovers the old case in which his father, an original-generation expert, was framed. Armed with irrefutable evidence, he brings the mastermind to justice and launches the "Night Watcher Protocol" to safeguard professional standards for grassroots tech workers.