Zhou Zheng, an emergency physician disgraced by a medical accident three years ago, takes a job as a night-shift caregiver at Yunlu, a top-tier nursing home. On his first night, Qin Zhenyue, a wealthy tycoon diagnosed with severe dementia, regains consciousness at 2 a.m. and begs him to stop the seventh injection. After saving the old man, Zhou discovers that the AI system has already generated a death report, while surveillance footage now shows fabricated images of him committing the crime. Yunlu's real business is helping Changqing Trust seize elderly residents' fortunes. Medication suppresses their minds, AI labels them as demented, and wills and guardianship transfers are then used to take their companies and properties. Alongside Qin Zhenyue and the other elderly residents, Zhou investigates from the underground pharmacy to the shareholders' meeting, exposing the old N17 case and Sheng Bainian's plan for the mother system.