Shen Youqing opened a dessert shop in Shanghai's French Concession. The cakes were delicious and the people were sweet. No one knew that she was an underground intelligence agent, and no one knew that she could hide film in the buttercream or write passwords in the frosting. Until Gu Yanqiu, the new section chief of the police department, came to the store to eat cake every day, and the eyes he stared at her became more and more uncomfortable. Bai Jinnian from the Military Police also came. He smiled and said, "Why does Miss Shen's cake always smell like blood?"
