China, 1941.
While war rages in Europe, Japan has established itself as the supreme power in Asia. Hangzhou, known for its beautiful scenery, has become a stronghold of the Japanese puppet government.
One day, five officers from the code-breaking department are escorted to a secret mansion outside the city. Their mission: find out who is the communist spy among them.
As each struggles to prove their innocence, the Japanese commander throws out a fake message hoping to lure out the under...