"This is our last chance!! Reiko, please...!" After retiring from her role as an undercover investigator to get married, Reiko Kobayakawa is drawn back into service at her husband's desperate plea. She infiltrates a casino operated by a criminal organization, posing as a guest to make contact with its high-ranking member, Sagawa. But her true identity remains undetected. When she attempts to arrange a meeting with Sagawa through a male accomplice, her actions are noticed by Sagawa himself. Soon, left alone with her target in a hotel room, Reiko is forced to confront Sagawa's true nature...