After his girlfriend's murder in Seoul, Tang Shuo joins detective Shin Jun-hyun to solve a series of locked-room murders. Though they catch a suspect, he suspects a larger scheme. With help from a journalist and a student, he stays in Seoul, using sharp deduction to uncover the true mastermind.

The film tells the female agent Ameera after a failed mission, private life crisis, conspiracy, and attempt to create organizational struggle Resident Evil dark story found during the processing of personal crisis.