Naval Commander Valerie Torres, the chief of logistics for a naval weapons station, collapses during a meeting. The OSP team tries to determine if it's a terror threat. Torres' husband Emilio said that she was concerned she was being poisoned. A review of surveillance by Sam and Callen reveals that Torres' top aides were affected as well. They both denied any problems. Sam and Callen suspect a microwave weapon. Torres wakes up and mentions a high-pitched sound. Then she becomes delusional again. Nell and Eric find the same van parked nearby both times Torres was attacked. They set up a monitor hoping to catch another attack. Nell and Eric determine that the same van had been previously parked outside Torres's house multiple times. Sam and Callen find the owner of the van and discover its license plates had been stolen. Another attack is launched and Kensi and Deeks approach the van, only to draw fire. The thieves push one dead man out then take off. The dead man was a twice-fired engineer who posted anti-immigration opinions. One of his associates was in touch with Torres's aide, Walter Purdue. Sam and Callen grill him. Purdue borrowed from a loan shark to pay for his son's rehab. The loan shark would excuse Purdue's debt in exchange for the schedule for cruise-missile deliveries. Drivers for a cruise-missile delivery get attacked with microwaves. The missile is stolen. The microwave weapon was left in their minivan. Nell and Eric track the truck carrying the missile to a nearby forest. The thieves still have another microwave weapon. Callen shoots out the weapon. The thieves try to escape in the truck. Sam finds a handheld missile and shoots in front of the truck, causing them to drive off the road. The team finishes up at Deeks' bar.