Lu Yuan, a standardized residency trainee in the emergency department, suffers grievances in the hospital, where his ex-girlfriend maliciously spreads rumors and frames him to climb up to a wealthy family, and his colleagues feel jealous and stab him in the back everywhere. Under the joint suppression of everyone, he is about to be expelled by the hospital, and his life falls to rock bottom. At a critical moment, the strongest residency system is unexpectedly bound, and the system can predict the life and death of patients in advance and accurately analyze various difficult and critical illnesses. Relying on the system and his own solid medical foundation, Lu Yuan repeatedly avoids misdiagnoses and snatches patients back from the hands of the death god. He constantly breaks prejudices and resolves exclusions, steadily improving his medical skills, and all the way counterattacking from a down-and-out, inconspicuous trainee to a hotshot core physician in the emergency department.