When a suspected North Korean spy is poisoned and hit by a truck carrying Christmas trees, the team must search for who is responsible for smuggling spies into the country. Also, Deeks and Kensi try to find a way to include their mothers in their Christmas plans, and Hetty notices that Granger isn't feeling the holiday cheer.

The team investigates the murder of tech entrepreneur turned venture capitalist who secretly developed a daemon, a background computer program that allows for undetectable data collection