1943, Occupied area of Paris.
Pianist Xiao Wange was forced to play for Nazi officers, but he hid Allied intelligence in the key of E flat;
Translator Xie Tingyun reviewed every performance, but folded the capital punishment order into a paper airplane and shot it towards the resistance organization's stronghold.
When Xiao Wange put his gun against Xie Tingyun's temple, he found that there was something in his pocket——
The ticket stub of the Vienna concert three years ago had written on the back: "The note you played wrong was the music stand that I knocked over on purpose."
"We share the weight of a gun, but the direction of the muzzle is always in the wrong direction."
Purpose: Female resistance in war