Former Harris County prosecutors Casey Garrett and Alicia O'Neill head to Flint, Mich., to help with cases that have yet to be processed for DNA evidence. They work closely with the Flint Police Department officers to track down a violent rapist who terrorized a family and another who lured his victim into his home.

A 17-year-old unsolved investigation into the rape of a teacher on an elementary school campus has hit a dead end. Casey and Alicia re-open the case files, and they uncover new leads that hopefully can put the man responsible behind bars.