The NCIS special agent afloat, Niles, aboard a fictitious aircraft carrier, USS Van Buren, dies of blunt-force trauma to the head aboard the ship in the Sea of Japan; one possible suspect is in the brig due to a fight in the crew's mess on the same day as the death; the fearless foursome fly to the ship aboard a CoD aircraft; G poses as the replacement for the dead agent, Sam as a Navy commander, Kensi as a Marine major, and Deeks as a computer contractor. Deeks gets into trouble but sees that Niles died elsewhere; the command master chief petty officer displays alarming behavior; the entire team chases a cocaine problem while more trouble brews; Deeks finds a pair of valve handwheels and runs into another problem; the whole team, including Eric and Nell, finish solving the crime. Hetty arrives aboard for Christmas, but Sam returns to Los Angeles in the back seat of a Super Hornet; Nell catches Eric under the mistletoe, then they head out in their tights and ears.
—DocRushing