Inseparable tells a multi-threaded and plot-twisting alternative story in a southern Chinese city. It combines plot and psychological suspense elements: Wu Yanzu plays Li Yue, a young engineer who is in constant trouble at work and at home. His wife, Pang (Gong Beibi), is a seemingly emotional undercover reporter, and Yan Ni plays his boss, who puts a lot of pressure on Li Yue. At the beginning of the story, Li Yue tried to commit suicide for various reasons, but was saved by his foreign neighbor, Lao Cha (Kevin Spacey), and the two became good friends. So they "ran out of control" and embarked on a completely unexpected journey in their lives together. But is Lao Cha really just an ordinary neighbor?