1939, Shanghai Gudao. Upstairs of an inconspicuous second-hand bookstore in the French Concession, the "Shadow", an underground party member, writes information with invisible ink every night. His public identity is that of a silent clerk in the archives department of Wang Puppet Secret Service Headquarters. When a top-secret list is accidentally exposed, he must protect the emergency evacuation channel code-named "Lighthouse" in the intertwined network of Japanese secret services, military lurkers and gang forces. Tonight, the flowerpot on his window sill was tilted to the left—a danger sign.
