After a bakery truck carrying a load of military grade battle rifles crashes, NCIS is called in to investigate. With the driver missing and several crates of U.S. Marine body armor found, they presume the truck is involved in the black market sale of military goods. While processing the vests, Abby discovers the entire batch is faulty and life-threatening for its user.
The investigation leads to a manufacturer's representative who admits to a batch of recalled vests, but claims they were all destroyed. They turn to a marine sergeant who lost the use of his legs due to a faulty vest he received a gift from his mother. It was part of a care package shipped overseas by a charity run by a woman who bought the vests from the truck driver without knowing they were faulty.
When the recall paperwork reveals the manufacturer actually profited from the recall, they question the representative again. He confesses to working with a gun show proprietor responsible for trafficking black market equipment and killing the truck driver to tie up loose ends after the crash. The team hunts down the proprietor and a showdown ensues. Bishop takes a bullet just as her shot takes down the proprietor who wore one of her faulty vests as a last resort, while Bishop's fully functioning body armor spares her life.
Meanwhile, McGee helps Delilah come to terms with her own disability and Palmer wrestles with superstitions about his impending adoption.