Narcotics Agent Ai responds to a colleague's call for backup, only to discover that the organization's boss is the man who once led her late father down a path of evil. Shattered by the revelation, Ai decides to go undercover alone to rescue her comrade—but is quickly captured and injected with drugs. Her consciousness blurred, she becomes subjected to intense, torture-like training. The story focuses on how Ai will overcome this brutal ordeal, regain her strength, and uncover the truth.