Fang Zhen Dong is a patrolling officer in Beijing who one night meets the drunk Li Pei Ru while singing karaoke at the KTV place. Li Pei Ru is a real estate agent from Hong Kong who has vowed to make her fortune in the cosmoplitan Beijing, but is caught up in the complexities of life and ends up becoming a mistress of a married man.

In 1948, as China's civil war reaches a critical point and the Kuomintang's economy collapses, Communist agent Fang Meng'ao goes undercover as an Air Force colonel. Assigned to investigate corruption—led by his own father—and later to help transport national assets to Taiwan, he becomes entangled in a complex power struggle. Caught between duty, family, and political shifts, Fang plays a pivotal role in a covert mission tied to the peaceful liberation of Beijing.