1940, Shanghai. Shen Shen was arranged by the organization to sneak into the Japanese military's special high school, and his mission was to steal a germ warfare plan. But as soon as the contact person handed him the information, he was shot to death randomly. Shen Mo ran into the alley and bumped into a woman wearing a cheongsam. The woman smiled at him and said "Follow me" in Japanese. The back of his neck felt hot, and his murderous intent was so strong that it was choking. But before he could take action, the woman handed him a key and said: Your father is still alive. The Japanese captured him just so that you could rescue him. Silence held the key and watched the woman disappear into the night. He knew it was a trap. But he must jump. Because there are three words engraved on the key - underground three floors.
