Entomologist Cheng Likun used specimen collection as a cover to weave a secret intelligence network in the occupied areas. His ultimate mission is to breed moths that can carry microfilm and allow this humble messenger to cross the Japanese blockade. When a key blueprint related to the war situation needs to be sent out urgently, Cheng Likun and his "Moth Shadow Project" are on the line of life and death. The arrangement of the specimen needles hides a code, and the flapping of the moth's wings determines the outcome. On the edge of science and espionage, a silent battle of life and death quietly unfolds.
