Dustin, a young boy, witnesses the murder of his aunt, Petty Officer Heather Cobb, by an intruder. Isler is taking Gregorio back to the FBI full time, and Pride offers her the open slot on his team. LaSalle and Percy find a suspect, former Petty Officer Josh Gordon, who attacked Chief Musician Robert Riley after Riley gave Cobb the first trumpet position in the Commodores, a Navy jazz band. Pride finds out Dustin is a trumpet prodigy. LaSalle and Percy find Gordon playing for tips, then have to chase him down. Dustin says Gordon isn't the killer. Gordon said Cobb had been going to the music academy at nights, which Dustin confirmed. Isler tells Gregorio that the Cuidad Natal cartel is laundering money in New Orleans, and they are going back to D.C. to brief officials. Pride and Dustin bond over music. Dustin tells Pride what he remembers about the night of the murder. Heather found PCBs in the soil behind Dustin's school. Dustin is coughing up blood, and Pride takes him to the hospital. There are PCBs in Dustin's blood. The FBI has flagged the file of Javier Garcia, who owns the construction company working at the school. Garcia is the front man for the cartel, buying up properties in New Orleans. Theo Beattie, the company's foreman, killed Cobb and is after Dustin at the hospital. He takes Dustin, but the team catches up to him, and he lets Dustin go when the boy can't stop coughing. Gregorio tells Isler that she's not sure she wants to stay with the FBI. Sebastian tells Pride that he wants to be a special agent. Gregorio overhears Pride telling Sebastian that he'll give him a job if he passes training, and tosses her application, returning to DC.