A training instructor is stabbed and killed. Pride visits Jimmy at his new job at a bakery. The dead woman is Sgt. Kate Dunn, an instructor for JROTC. Mateo Diaz is identified as a person of interest and is missing. Mateo works at the same bakery as Jimmy, and Jimmy gives them a place to look for Mateo. Pride and LaSalle find him, then NOPD sweeps in. Mateo is a confidential informer for Officer Carter, who is investigating the Aztec Kings gang. Mateo says Dunn tried to help him escape the gang and introduced him to Carter. They have to release Mateo to Carter. The gang is suspected of killing Dunn. Pride and Hannah confront Leo Reyes, who was looking for Mateo at the bakery that morning. After Pride warns Leo to leave Mateo alone, Pride and Hannah are fired upon. Mateo ended up at an ICE detention center and Carter is missing. All of Carter's Aztec King arrests get reduced charges, as evidence disappears. Carter was found dead in the park, killed by the gang. Mateo is being followed in the detention center yard, but Pride rescues him right before he is knifed. Pride is getting in trouble for skipping out of meetings, although Steven tries to cover for him. LaSalle threatens Gordon, the guard the gang has bought off. Another corrupt guard tailed Pride and Mateo. The gang surrounded Cassius's old fishing cabin where Pride, Jimmy, and Mateo are hiding out. Pride sends Jimmy and Mateo out the back, to head for the highway. Mateo twists his ankle. Pride runs out of ammo, then takes down the first two entering the cabin. Mateo holds Leo off with a gun, then Pride shoots him. Hannah and Gregorio show up afterward. Loretta is going to find Mateo a foster family.