After a car accident, ordinary girl Emily is admitted to hospital and suffers hallucinations, constantly seeing another version of herself in mirrors. Brilliant neurosurgeon Vivian takes charge of her case and shows unusual concern for Emily. In truth, Emily infiltrates the hospital to investigate the suspicious death of her sister Lina, who died during surgery three years ago.
Helen, chief of psychiatry, schemes behind the scenes. She tries to frame Vivian by manipulating Emily, falsifying surgical records and planting recording devices to drive a wedge between them. Vivian soon sees through the trap. Instead of exposing Emily, she forms a secret alliance with her to dig into the old surgery case.
Suspicion fades and romance grows as they test each other and investigate side by side. They uncover Alen, who helped tamper with medical data, and gather solid proof showing Helen fabricated evidence to shift blame. The full truth comes out at an ethics hearing, and Helen is convicted for her crimes.
With the wrongful case resolved, Emily lets go of her desire for revenge. Vivian leaves the public hospital, and the two open a private neurology clinic together. In front of Lina’s tombstone, they confess their love, heal past wounds and build a peaceful future of their own.
