The BAU is called to search for a man who is targeting children when an eight-year-old is found murdered on the Appalachian Trail.
Much to Bell's dismay, Nic and Conrad decide to admit a homeless Jane Doe, whom they suspect was dumped off by another hospital during Chastain's big Charity Ball.
Torres is forced to revisit her troubled past when her half-sister is incarcerated in a juvenile corrections facility.
After all the guests attending an upscale fundraising soiree for the science department at a local university fall ill, the CSI team gears up to investigate; Catherine enlists Grace's roommate to help her find clues after Grace disappears.
Mike and KITT must drive faster than 100 mph to keep a bomb in the trunk from exploding; Sarah gets upsetting news about her father.