A low‑rank worker at an advertising agency, dying of a heart attack after endless overtime. Opening eyes again, hearing a robotic system voice in the mind: “The Space‑Time Repair System is bound. Travel to Shanghai in 1937. Protect intelligence agent Shen Zhiyan within 48 hours, retrieve intelligence of Operation Nightingale, and stop Gu Yanzhi from handing it over to the Japanese army to gain a new life.”