The military's ace agent Shen Xiao, codenamed "Gray Fox," is ruthless and feared by everyone. The only weakness is Chen Mo, his sworn brother who is an underground party member but shares life and death with him. When Chen Mo was "betrayed" and sacrificed in an explosion, earning eternal infamy, Shen Xiao was also trapped in the last 24 hours before his brother's death. The time loop began, and he struggled again and again, trying to reverse the ending, but he could only watch his brother die repeatedly in various ways. In the endless reincarnation, Shen Xiao went from the initial frantic rescue to the calm layout, using his omniscience of the timeline to deal with the ghosts of the military commander, the Japanese army, and the underground party. What he wants to do is not only to save a life, but to clear his brother's name, inherit his ambition, and complete an impossible "whitewash" in a desperate situation. When the cycle ends, the one who survives will be a brand new "grey fox".
