A group of young women are mowed down in the park with an automatic weapon and many are killed. Briscoe and Green manage to track down the misogynist offender, but it is hard to build a solid case. In consequence, McCoy and Carmichael attempt to prosecute the manufacturer who supplied the gun. Ground for the charge is that the gun is very easy to convert to full-automatic, using instructions and parts that can be picked up at any gunshow.