Yuki is a manager who is serious and strict when it comes to work. One day, she goes on a one-week business trip with Yoshino, a subordinate she is training, to inspect a factory in the countryside. She leaves her husband behind for the business trip. She travels from her accommodation to the factory by train on an unfamiliar train, but the train is just as crowded as in the city during rush hour. While on the train, Yuki is molested. She calls out to Yoshino for help, but he is nowhere to be found at the most critical moment. The molester appears every day as if he is targeting Yuki, and the acts escalate. Yuki has no idea that he is a subordinate and a worker at the factory...