ER Doctor: My Sister's Best Friend Has Been Clinging to Me from the Start

Lu Zhou, an emergency room doctor, is publicly betrayed and dumped by his girlfriend of many years. He unexpectedly sleeps with Su Muhan, a stunning, icy woman, and awakens the Medical God Evolution System.

With a single glance, he can see the source of an illness, and hands-on surgical experience can raise his medical skill level.

His ex-girlfriend and colleagues make things difficult for him at every turn. Backed by the deputy director's influence, they sabotage him, spread rumors, and try to drive him out of the hospital.

A chain-reaction car crash suddenly occurs. Lu Zhou steps in during the emergency and accurately assesses the injuries of critically wounded patients with nothing but his eyes. He predicts a concealed intracranial hemorrhage, but his judgment is questioned.

In the end, the patient falls into a deep coma and suffers an acute cerebral hemorrhage. Just as everyone is preparing to give up, Lu Zhou uses the System to pull the patient back from the brink of death, proving everyone wrong and leaving them all in awe.

The new director, Su Muhan, begins to feel drawn to him, completely unaware that Lu Zhou is the man she had a one-night stand with.

A series of missed connections and misunderstandings outside the hospital keeps them from learning each other's identities.

Inside the hospital, they always wear masks. One coincidence after another leads them to miss each other repeatedly, and they never meet face-to-face.

In these circumstances, Su Muhan is repeatedly impressed by Lu Zhou's abilities, and eventually falls for him.

Then, by chance, they meet, and all the misunderstandings and coincidences are finally cleared up that day...