It's about to be Christmas in NCIS land... but not everyone's looking very merry in photo CBS has released from NCIS Season 11 Episode 11.

When children from military families become ill, the unit teams up with Naval Medical Research to figure out the cause and find a cure before it ruins everyone's holiday.

And as if the first holiday season without his wife wasn't difficult enough, Director Vance must find a way to make things work with his estranged father-in-law.

Click through the photos for the coming installment airing on Tuesday, December 17 and don't forget you can always watch NCIS online right here at TV Fanatic.