Danny and Jamie join forces with their nephew, Joe Hill, when Jamie and Joe's search for an undocumented teenage girl who has been sex-trafficked, converges with Danny and Baez's investigation into the murder of a woman in witness protection. Also, Frank and Erin butt heads when Frank calls out the District Attorney's office for instituting a new rule that classifies armed robbery as a misdemeanor, a mandate that has immediate ramifications for Eddie and her partner.