It's about a former professor of English in a German University in China named Yu Tsun. He is also a spy for the German Reich on a mission to tell Berlin the name of a town in England where the British are hiding an artillery unit. A man by the name of Captain Richard Madden is trying to catch Yu Tsun before he does what he has to do to get the message to Berlin. Yu Tsun finishes his mission by finding a man with the same last name of the town where the artillery unit is being hidden and killing him.Then the following day in the media Berlin has the name of the town. Yu Tsun's victim is the man Dr. Stephen Albert, and while Yu Tsun is at his house he learns that Stephen is a lover of Chinese culture and literature and has remade a labyrinth text written by Yu Tsun's ancestor Ts'ui Pen. After seeing this test Yu Tsun askes Stephen to see it again, and when the man gets up Yu Tsun shots him in the head. Moments later Captain Richard Madden barges in and arrests Yu Tsun. But Yu Tsun does not care because he has completed his misson.
