Before Christmas, Hetty assigns Callen the case of his former foster brother and his wife who, upon reentry into the U.S., are framed for smuggling drugs across the border in her oxygen tanks. Also, Deeks is struggling with losing his job at NCIS.

The NCIS team's murder investigation of a man who sold military information leads to the abduction of a doctor whose cutting edge neurotechnology could be developed into advanced weaponry. Team members are interviewed by FLETC to see if Deeks would make a good NCIS agent. Callen tries to have an important talk with Arkady.

While NCIS must track down an organized crime leader who is trying to buy stolen defense technology, Callen goes to Anna to ask the ultimate question. Also, Deeks is kicked out of NCIS training only to find that Hetty has a life-changing surprise for him.

When Sam’s daughter Kam is kidnapped after leading citywide protests he will stop at nothing to find her. Also Deeks rejoins NCIS and Callen searches for answers about Anna

After Callen receives a cryptic message from Hetty, he tracks down the person tailing him, bringing him to a remote location teeming with Russians… and face to face with Anna.

When a petty officer is found dead with an apparent suicide note, the NCIS team must investigate the mystery surrounding his death. Also, Callen and Anna begin wedding planning and Sam has a heart to heart with his daughter.