Scott Reid, Lance Hamilton's partner, gets killed in a parking garage. Kilbride is making Callen take his accumulated leave. Instead he's following a woman. Deeks and Kensi argue about the virtues of country music. DOJ is investigating dirty federal agents. Kilbride asks Sam to reactivate his undercover persona Switch, to draw out Lance's suspect, Percy Vander, Switch's mentor. The rest of the team is investigating Ryan Logue, an aerospace engineer who stole classified Navy schematics. Sam calls King to make sure his Switch persona is still viable. Kensi and Deeks approach Henrik about the schematics. Callen is tailing one of his former foster mothers. Sam and Lance rob a Korean biker gang to get Vander's attention. Kensi and Deeks tell Henrik he's going to help them locate Amantas. Roundtree brings in Logue for Kilbride to interrogate. Lance worries that Sam may still be too close to Vander. After Kilbride let Logue sweat, she's ready to talk. Sam meets with Vander. Logue says it's all Amantas's plan. Kilbride knows she's lying. Amantas denies knowing Logue to Kensi and Deeks. He says she contacted him and gives them a dark web site to check out. Sam asks Vander about the missing notebook with dirty agents' names in it. Vander's men pulls guns on him. Sam takes out one, Lance the other. Vander goes out into Lance's sites to be shot rather than be arrested. Amantas was right about the web site. No criminals would trust being approached out of the blue by someone selling stolen documents. The notebook is recovered. Callen remembers the foster mother handing him over to Hetty.