At a police debriefing, which Kenji and his partner Banba are attending, it is revealed that the kidnappers could have connections to Samuel McCoy. Amidst rumors that his profitable chain of nightclubs and restaurants is a front for a lucrative prostitution and sex slave ring, it has been impossible until now to find any hard evidence. Kenji and Banba are ordered to interrogate the prisoner and get "something that'll stick on McCoy's Teflon ass".
During a brief stop into the office where Maki is filing her incident report, Kenji sets up a date with Maki, and informing them of the pending case against McCoy. The news on McCoy, naturally, disgusts the three girls, but is quickly forgotten amidst Kenji and Maki's flirting, drawing up envy among the girls.
This date, however, is later interrupted by Banba bringing late news about the case. Despite Maki and Kenji's chagrin upon being interrupted at a very awkward moment (Maki wrapped in a towel after a shower and Kenji was in his briefs), they listen as he tells them they have had many sightings of missing women at one of McCoy's clubs, the Sartrait 7. Kenji declares it too dangerous, and outright forbids Maki to investigate. Date terminally interrupted, Maki brings Kenji back to the station to question the prisoner.
However, when Kenji goes to interrogate the captured kidnapper, as ordered, he is shocked to find the man dead in his cell, poison needles peppering his body. This prompts the team to, reluctantly, investigate their only remaining lead, the Sartrait 7.
While mingling with the crowd, Yuka stumbles upon a lonely, sad-looking girl in a frilly yellow dress, and goes to befriend her. The girl sobbingly confides that she was expecting her boyfriend, but has been stood up. Yuka offers to keep her company, keeping her safe and attempting to pick up her spirits by buying her a soft drink. However, at the vending machine, she is attacked from behind and subdued by a muscular thug, with the frilly yellow-dressed girl suspiciously acquiescent.
The thug is followed by Remi and Maki, who draw weapons and hold up the kidnappers. All goes well, until a muscular figure sweeps out of the shadows, with dark, almost slate-gray skin and long red hair. with shocking agility for a man his size, he leaps away from their every attack, throwing a hail of poison needles -the same as that which killed their prisoner- at them, knocking the girls unconscious.
At the hospital, the poison is neutralized and their wounds treated, and Kenji comes to tell them that they can't officially investigate the kidnapping of Yuka at McCoy's club, due to the lack of evidence. Even the presence of the red-haired killer -identified as Gonnack, McCoy's bodyguard and suspected assassin- isn't enough to issue a warrant on McCoy.
Maki decides she's going to take matters into her own hands, using her Junior SWAT clearance to take what she needs from the armory, behind the chief's back. Remi reluctantly assists, and rigs an alarm to distract the security in the police garage. They steal a police assault carrier and make for McCoy's mansion.
Meanwhile, Yuka is imprisoned in McCoy's basement, awakening in a cell with three other young women. Here, they sobbingly confirm that they are being groomed to be sex slaves to be sold off to the wealthy, with compliance or suicide the only possible escape.
In step two of McCoy's henchmen, headed by Ryuji, who tosses Yuka's badge on the floor, demanding answers. She resolutely defends her cover that she was off-duty and only there to have fun, despite being stripped to her underwear and whipped repeatedly, enduring the shame and pain, firmly believing her department will help her. Upstairs, McCoy mildly scolds the little yellow-dressed girl, Sayaka, for bringing a cop to his operation, while seemingly proud of her as well. Sayaka merely grins smugly, quite proud of herself as well, despite the danger.
As Maki and Remi lead a precision two-woman commando raid on the base, with the assault carrier on auto-pilot as a diversion, Kenji discovers their absence and demands the chief take action to rescue them. The chief cites police policy at him until gunfire is reported at the mansion. Finally having had enough, Kenji declares that he's going in as well, and the chief can discipline him when the smoke clears. Finally consenting to the raid, the chief orders the Senior SWAT division to go in, rescue the girls from McCoy, and the department from embarrassment at this rogue action.
Eventually, Maki and Remi learn the girls' location, and break Yuka and her cellmates out. Ordering the unarmed Yuka to lead the girls to safety, Maki and Remi press on to arrest McCoy. The women are waylaid, however, by an apparently panicked Sayaka, who runs into them in the hallway as she and McCoy try to escape the besieged compound. While she has them off guard, McCoy and Ryuji draw weapons and fire, wounding the two officers.
Meanwhile, the SWAT reinforcements arrive, and Kenji himself appears in a helicopter, tracking the girls' location. He and Banba sneak in behind McCoy through a skylight, killing Ryuji and surrounding and arresting McCoy. He rescues Maki and Remi and, as she says herself upon fade out, "that's that."
Later, after the credits roll, Yuka visits Remi and Maki in the hospital and inquires as to when they would like to return to Sartrait 7. Both officers nearly fall out of their beds from the shock, leading Yuka to claim she was only joking.