In the thirty-first year of the Republic of China, Peiping fell and was in turmoil. Shen Qingqiu, the proprietress of the old teahouse "Qingyaju", relies on her superb tea skills and unique skills of observing people to distinguish between loyal and traitorous people and judge people's hearts on a small tea table. She secretly delivered information to the underground party, but during a meeting, she unexpectedly met Lu Tingshen, a traffic officer codenamed "Hongyan". From trial to trust, the two used the teahouse as their base, and under the close supervision of the traitor spy leader Zhao Deli, they cleverly passed on intelligence and resolved the crisis many times. A cup of tea can reveal all kinds of things in the world; a secret message can hide the great interests of the family and the country. In the spy battle with swords and swords, Shen Qingqiu and Lu Tingshen also developed a restrained and deep tenderness in troubled times, and together they guarded the city's spark of hope.
