A gang of young thieves try to rob a mob boss, but their heist is interrupted by an officer of the Tokyo Police Department's elite Zero Division. They get away with the loot, but the officer, a beautiful, more-than-slightly psychotic young woman who also happens to be an excellent shot, is tracking them down. To bring the case to a successful conclusion, she must deal with rival crime gangs, small- time crooks, and the wavering loyalties of her own partner.
It's Christmas Eve in Tokyo as Ichiro is moving into his new apartment one month ahead of schedule. As he is getting settled in, two strangers enter the apartment and are surprised to find him there. They begin complaining that he is upsetting their plans for a Christmas party to be thrown in the apartment that night before attempting to kick him out.
Yusuke Mikuni, a department manager at his company, buys a one-room apartment to have some space to himself. He signs an agreement with a young woman named Chako and has an affair with her once a week at the apartment.
