The NCIS team takes on a renowned hacker who could hold the key to tracking down the most-wanted cyber-terrorist in the world, on NCIS.

Gibbs and McGee travel to Russia to safely escort home an NCIS computer engineer connected to classified intel, but their mission is compromised and they are forced to go off the grid while hunted by a Russian mercenary group. Meanwhile, the team in D.C. frantically uses every asset and inter-agency contact they have in an attempt to locate their missing team members.

The NCIS team consults with three cyber-terrorists they imprisoned after a city-wide Internet shutdown the week before Christmas. Also, McGee reflects on the case and Gibbs' infamous rules as he pens a heartfelt letter to his father.