Once a brilliant neurosurgeon but now a pharmacist in a rural town, Se-ok still performs brain surgeries at night. Se-ok is confronted by Deokhee, the mentor who had a hand in stripping her of her medical license and ruining her life.

Deokhee wants Seok to operate on him for a tumour in his head, but Seok does not want to comply with her mentor's request. Frustrated by his former pupil's reluctance, Deokhee puts pressure on Seok.

Seok wants revenge for what Deokhee did to her and meets Nanae in the hope of stopping Deokhee from winning the Ichida trophy, an award he is poised to win for the tenth consecutive year.

Seok is in search of Deokhee's weaknesses. She visits a former patient, Kim Myeongjin, who is the main reason for Deokhee's betrayal, and asks him why he wanted to erase her from his life.

Seok's past comes back to haunt her when Doobong, a former patient, calls and warns her of a threat coming her way. To make matters worse, a sudden house fire pushes Seok to the edge.

A rich patient requires a highly complex surgery that needs two skilled neurosurgeons. Deokhee comes on board, taunting Seok and telling her he wants to see what her world is like. Stuck with no other choice, the two reunite at the operating table.