Charles goes undercover among gang members from his old neighborhood when it's discovered that they've been stealing explosives and weapons. Meanwhile, Tiffy gets hurt at work and Mack goes after her attackers.

Brian Majestic, Christina Gianaris, Enver Gjokaj, Frankie Rodriguez, J. J. Dashnaw, Jarrod Bunch, Jorge-Luis Pallo, Jose Pablo Cantillo, Larry Bates, Nick Toren, Roberto Montesinos, Stana Katic, Yara Martinez