Isler is running an opioids theft investigation, off the books. He gets busted and calls Pride for help. He recruits Pride for the operation. Isler has a file for a dead petty officer who died from an opioid overdose, so NCIS can take over the investigation. They search for Bellanger, who is part of a theft team. Sebastian has them check auto-repair shops for Bellanger's Charger. LaSalle and Gregorio find the right one, and LaSalle drops a car on Bellanger's arm. Pride and Isler con him into giving up what he knows about the job before he can see a doctor. Bellanger takes Isler and Percy undercover as part of the robbery team. Isler convinces Cranston, the team leader, that he's legit. The robbery is happening right then. An unknown man, Charlie, is giving orders to the team. Pride suggests the leader may be a dirty cop because of the detailed information to which he has access. The theft goes down, and an injured Cranston, Isler and Percy escape after a firefight in which Gregorio gets injured and one robber gets killed. Patton thinks the leader is Driscoll, a retired FBI agent from Atlanta. Cranston is still suspicious of Isler and Percy. Pride and Sebastian break into Driscoll's house, but it's only a relay station. Cranston dies, but Isler still wants to bust Charlie. Driscoll and Isler recognize each other, but Driscoll gets the drop on Isler. Pride and Sebastian break in on the scene. Driscoll tries to back into traffic to escape, but gets sideswiped and killed by a semi. Isler gets called back to D.C., and invites Percy to call him if she ever wants a change. He tells Pride he'll look out for him in Washington.